yashsingh1/xdaforums huggingface dataset:
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] D-m-x:
Are you using a Substratum Theme or something? Only App I know is Tapatalk that has issue with Magisk.

Gesendet von meinem SHIELD Tablet K1 mit Tapatalk
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Az Biker:
Which Magisk are you flashing, and you're flashing it in TWRP?

What is your exact setup?

8.1 factory image?

TWRP?

Magisk version?

What was the setup the last time it worked properly?
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] fKm:
No, I don't use Substratum right now.

I am using Magisk v. 5.13 and flashed it via TWRP.

8.1 factory image from January and stock kernel for testing right now.

TWRP version 3.2.1.0

I never had any setup that worked before. The first day after arriving of the device I used it without root. Later I unlocked the bootloader (critical), reflashed the factory image, flashed TWRP and the latest Flash Kernel and Magisk. After that I got the FCs. Without Magisk I don't get the FCs.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] clothednblack:
You did both bootloader unlocks, right? I see you mentioned critical only

And I'm guessing you meant Magisk 15.3
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] fKm:
Yeah did both unlocks and meant Magisk 15.3.

After further investigation it seems that Xposed Framework is causing the problem. Gonna do further test but that has nothing to do with Magisk then. Thx for the help guys.

Edit: With systemless Xposed via Magisk it seems to work. I don't have FCs with installed systemless Xposed.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Az Biker:
Generally, before reporting any issues, Xposed should be removed first, as it does tend to break a lot of stuff :D
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] CyberpodS2:
Not to mention it would have saved everyone a few posts if xposed was mentioned from the start. The more info you can give the easier it is for folks to help. But on the other hand, thank you for following up with the details that for you fixed up...
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] fKm:
Yeah, that was definately my mistake, sorry again. I just didn't remember I installed Xposed :silly:

Btw: Even with systemless Xposed I got some problems, so beware. I just gonna wait until Xposed for Oreo is stable.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] unatco99:
Using Magisk on 2 different Pixel 2 Xl's whenever I install any module, upon reboot I get a message "There's an internal problem with your device. Contact your manufacturer for details". Any module I install gives this error, I'm installing magisk manager, then patching the boot.img from taimen-opm1.171019.013. I then reboot to bootloader and flash the patched image using fastboot flash boot_a patched_boot.img, fastboot flash boot boot_b boot.img. Can anybody give me a clue of where I'm going wrong? Using Magisk Manager 5.5.5 and it installs Magisk 15.3 when it patches the boot image. This is driving me crazy as everybody seems to be having great luck with this, but I'm clearly doing something wrong with this.

Modules I've tried that give the error,

Tethering enabler

Unified hosts adblock

Ainur JamesDSP

AM3D Ziren Sound

F-Droid Priviledged Extension

Xposed Framework

I'm not installing these all at once, but factory resetting, then trying a different module, then factory resetting etc. The only settings change I'm making in Magisk is for update notifications and Systemless Hosts. Thanks for any advise!
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Az Biker:
This is a widely known, well documented issue, look through the OP.

Please, use the SEARCH function (top right of the thread) and you'll find that many questions and issues have already been addressed and/or solved.

I Searched: "There's an internal problem with your device"

and got these
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Pkt_Lnt:
ninj'da ;)
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Az Biker:
Looks like you REALLY are from SLO :p
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Pkt_Lnt:
touché :highfive:
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] derekr44:
-removed-

I think I actually fixed it on my own
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Az Biker:
Fellow Arizonan! Hit 86-degrees here today... Probably really nice in your neck of the woods.

Just a suggestion; next time you have an issue and resolve it yourself (kudos by the way) , leave it up for all to see, because you never know who might have the same problem and would totally benefit from your post :D
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] THEbigSWEEN:
Off topic, but I was so enraged by your post I had to say something, Mr. "ooohhhh it's 86 degrees here!" as I sit here in Ohio where there's snow on the ground and will be single digits with the wind chill tonight. I dislike you immensely, but purely because I'm EXTREMELY jealous... :p
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Az Biker:
Don't hate, my fellow Buckeye! I survived the great blizzard of 78, and the big but not-so-great blizzard of 82!

Born and raised just east of Cbus ( until I joined the Marine Corps in 85)...

You may continue your jelly-fest :p
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Pkt_Lnt:
So SLO (coastal CA) was hotter than the desert! Sorry Ohio. :p
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Az Biker:
OH! I got it now... I thought SLO was a diff way to say St Louis... 89 is HOT for your area...
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Badger50:
You gotta get outa the sun bro! Stl is St..Louis! My home town. Had a blistering high of 27 today :cool:
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] CyberpodS2:
Lol
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] derekr44:
I thought about that too, but this one was so off the wall. It basically came down to this: when you revert back to stock for whatever reason, force flash stock with flash-all.bat to both slots. My issues stemmed from the fact that things were left over in the opposite slot.

And yes, it was really nice over the weekend ?
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] CyberpodS2:
This has actually been a part of several threads now. I'm wondering if in the long term we are going to see Custom Rom installation scripts flashing to both sides as a regular function.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Az Biker:
I'm willing to bet it will be automatic... I've yet to specify A or B when flashing anything on the 2 XL. So hopefully, it'll be automatically implemented in cust roms as well :D
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] derekr44:
That's good to know, and I will be more mindful of that in the future. I couldn't find anyone that had the same symptoms, and I actually fixed it by accident because I wanted to get a decent logcat with nothing else on it.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] jr45:
I know that but any thoughts on why? Should I just try again or did I miss something?
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Khanbad:
When I run "fastboot flash boot patched_boot.img" it just sits saying "<waiting for any device>". I'm unlocked and think I did everything up to that point correct, am I doing something wrong?
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] mrlamotte87:
This worked perfectly! Confirmed working on 8.1.0 Dev 1 Preview. Just grabbed the Stock Image from the Developer site (linked all through this topic, sorry I don't have it handy). Thank you! Can't wait for even more development!
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] clothednblack:
same here, I am trying to find out why. If I figure it out, I will let you know
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] wonderrx:
Thank you for the instructions, worked great, including installing tether module in menu of magic along with busybox. I suggest someone add this to the first post in this thread.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] jr45:
do fastboot devices to see if it's reading in fastboot. If not you need to go into device manager while in fastboot and find the yellow triangle, right click, install driver.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] fixxxer0:
so everything worked fine for me doing the 8.1 dp1 root with the appropriate image...

tried this on my new RMA device running 8.0 with nov5th update using the OPD1.170816.010, Sep 2017 image and now im stuck on G booting logo. ut oh.

any advice?
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] jr45:
Still in bootloop after flashing factory boot.img. Any help is greatly appreciated.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Snow02:
Donated. Thanks for the work on this.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] clothednblack:
it sees it, and adb also boots me to bootloader, but nothing once in bootloader. unlocked when I first got this phone no problem

checked in device manager anyways and sure enough, yellow triangle. updated and fastboot did its thing. Thank you!
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] linezero:
anybody tried it on the November update over OTA? I went into a bootloop
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] bd177:
Try a different usb port on your pc or a different cable.

I see you fixed it. Disregard. Carry on.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] clothednblack:
fixed, scroll back from here. It is in the device manager on the PC, android needed an updated driver
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] fixxxer0:
yep, same happened to me. doh!
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] eudemonky:
great work！
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Khanbad:
Thanks for tagging me back.

When I go to update the drive, it says that it cannot find a driver for it? is there one that I can download? I haven't had to do this in 3+ years. I do appreciate the help.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] fixxxer0:
i tried flashing the 8.1 DP1 image from fastboot using the flashall script and got an error about wrong bootloader, needed to be on TMZ11 or something, and im on 10n.

its not letting me flash the original boot.img from the sept2017 image for some reason. saying no such file... wtf....
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] bd177:
Probably because you need to patch the boot.img that's in the ota. As of now the ota is still not up on the site.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] fixxxer0:
so in the meantime, how do i get back to a working phone
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] js042507:
Flashing the stock boot.img (unmodified) should fix a boot loop. However, did you maybe flash the bootloader.img previously with magisk? If so, that could have screwed things up. Flash the stock boot.img and bootloader-taimen-tmz10n.img. See if that gets you going and start from scratch. Make sure your fastboot commands are appropriate to the image type your writing though.

---------- Post added at 06:30 AM ---------- Previous post was at 06:28 AM ----------

Like bd177 stated, you need to flash the original boot.img via fastboot, but for the version of Android your system is running. 8.1 boot.img should be posted somewhere? Not sure. I haven't messed with 8.1 yet.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] derekr44:
Oh, and I wanted to show off a little before it hits three digits in a few weeks.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] dredq:
Hate. Hate you all.... :) It is 16 degrees here in Maine and been snowing all day....
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] THEbigSWEEN:
That's crazy, I'm in South-East Columbus! I guess since you're also a Buckeye and know and have lived the struggle of the "white death" (crappy snow) I'll let the temperature flaunting slide.... this time! :cool: Thankfully both those blizzards were just a little bit before my time. And I'm sure you just miss Ohio weather and sometimes getting all four seasons in one day lol

---------- Post added at 10:40 PM ---------- Previous post was at 10:32 PM ----------

What weather app is that in your screenshot? I see it references Accuweather, which is what I use, but mine definitely doesn't look anything like that! I assume it's a different app, just using Accuweather as the source?
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] CyberpodS2:
https://xdaforums.com/moto-maxx/themes-apps/moto-z-command-center-widget-t3417171

I think that'll get you the download, if not I'll shoot it over to yah.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] derekr44:
That same issue popped up again today, with some apps not connecting to Google Account Services and VPN/Hotspot traffic not passing through. I'm really beginning to dislike this A/B setup, and thinking flashing to both slots might prevent some of this from happening. It's strange, and I don't know if I'm contributing to the cause or what. I may spend time this weekend doing pure clean flashes and going from there.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Az Biker:
Whenever I hear users mention flashing both slots or just the a or b slot, it makes me wonder why I have never had to specify a slot when flashing anything. Since day one, I have never manually picked a slot or used a command to flash into a certain slot?

I wondering what is diff about the setups that do and do not specify slots....
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Az Biker:
[MENTION=3730810]Badger50[/MENTION]

Congrats on the RC!!!

You've been extremely helpful in several device forums simultaneously, and you fully deserve RC.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Badger50:
Thank you very kindly my friend. Couldn't have done it without your guidance. I'll try my best to be a good one??
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Pkt_Lnt:
That's great! Welcome to the green world. :good:

I was thinking you should change colors and was just investigating the process. Glad someone beat me to it! :highfive:
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] derekr44:
I don't really know. I didn't have an issue with sailfish nor with taimen until just last week. So I'm just trying to make an educated guess with the little I understand. Thinking out loud, I suppose.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] CyberpodS2:
It seems to be mostly connected to folks failing at installing the couple custom roms I think. I have not taken the plunge yet but it appears the inactive partition is being bored after the flash. At least that's what I am taking it as. So my thought was of there is any chance of boring to or even installing to the wrong (out of date) partition then flashing both sides on initial install would eliminate that. Or am I thinking of it in the wrong way?
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Badger50:
Thank you kind sir. I don't really know what happened. Someone went HULK on my title! ???
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] joeyddr:
anyone update to the latest feb release getting response is invalid now when checking safety net?
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] zrepiV:
I am also getting this
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Badger50:
https://xdaforums.com/apps/magisk/mod-magisk-v1-universal-systemless-t3432382/post75468865
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Az Biker:
I just checked after reading these, and my Safety Net passes.

Feb factory img

TWRP

Flash 2.16 kernel

Magisk 15.3
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Badger50:
Yeah, the servers were down for a bit. But it's all good now ?
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] DudeThatsErin:
For some reason my Magisk Manager looks like the attached picture.

Anyone have any ideas why?
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Az Biker:
I would think because you're still on Magisk 14.4?
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Surge1223:
If you have one boot.img on Feb patch and the other on Jan, twrp loses its crap and decides to have a fit and stay on splash until you give it a boot.img that has the ability to use Dee's ancient kernel init rc scripts.

Seriously 4.4.55 kernel lol

You can get around this manually in adb by mounting system and data and starting hw services and key store

You can get around decryption issue on Feb patch via adb at twrp splash too so it decrypts, but it's a pain to do and explain
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Az Biker:
Thanks for the answer!

So how have I been fortunate enough to never have TWRP lose it's mind, when I've never made any commands or selections regarding either slot?

I'm presuming that this is done automatically during the flashing process?
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Surge1223:
Except for when magisk doesn't know when dtbo isn't stock, for example It always backs up my dtbo that isn't stock and says it's backing up stock dtbo.

Flashing magisk right after I flash stock dtbo.img to both slots seems to keep the errors away.

---------- Post added at 04:03 PM ---------- Previous post was at 04:01 PM ----------

Most of the time, however twrp sometimes doesn't have the ability to tell bootctl Hal boot into the other slot, and ususally the only way you would to worry about other slots is if you flash a rom or Ota since it does it automatically during this, and twrp doesn't ususally catch on (that's why the a b switches in reboot twrp menu are godsend)
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] DudeThatsErin:
There is an updated one? I'm going to look for it now.

EDIT: Even this thread is v14.4(4444)... so I'm not sure what you are talking about.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] galaxys:
V15.3 (MM5.5.5) latest...go to Magisk Beta thread.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] DudeThatsErin:
Thanks! Idk why it isn't posted here. Weird.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] galaxys:
Think because there are so many devices, updates, etc. that he centralizes everything in the Magisk Forum.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] DudeThatsErin:
I'm still getting SafteyNet API Error. Any ideas why?
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Az Biker:
Mods? Xposed? Magisk modules? SU hide not checked in MM?
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] DudeThatsErin:
SU Hide? Do you mean Magisk hide? Yes, that is enabled.

No Xposed (didn't even know that worked yet). No modules or mods besides ElementalX.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Lw00d:
hi guys just want to confirm something..

im going to adb feb factory image..

to get root.. just need to follow the Magisk steps right?? dont need trwp?

i have root.. just old build november
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Alxoom33:
Yes
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Lw00d:
thank you sir
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] elmemyself:
Hi guys. I have my device rooted with the most recent magisk manager + magisk, up to date twrp, etc. Is it possible to update from January's built to February's without losing anything? I'm referring to root related tweaks etc. Thanks.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Badger50:
If you fastboot the factory image with the -w removed from the flash-all.bat script, let it boot up, then remove you fingerprint/pin/password lock screen security, then fastboot twrp, once in twrp, flash the twrp.zip, custom kernel.zip(if used) then flash magisk.zip........you won't lose anything ?
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] mayorblurps:
It IS posted here... see the main page of this thread, in bold red at the very top:

Pixel 2 (XL) is now officially added on the Magisk support list, please install Magisk v14.5+. These builds here are deprecated

Check out the latest beta from the official beta thread
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Az Biker:
Unless there's a specific reason you're using an earlier version, just download 15.3 here :D
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] mayorblurps:
Oh absolutely. I was pointing out to the OP that this thread is deprecated, and says so on page 1.

I'm current with the latest Feb release, TWRP, Flash kernel and Magisk 1531 thanks to your fantastic instruction post.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] gtaelbordo:
deleted
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Yasharkhan:
HEEEELPPPP

its the 4th time i am posting regarding this issue and i have not found any help. i am on ANdroid 8.1 latest feb security patch now with 15.3 zip and 5.5.5 apk installed with Flash Kernel. my problem is that no module is sticking, they get installed but after reboot they disappear. what is wrong? and can anyone please help me?
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] quinejh:
That's strange. I have the exact same setup as you described and its working flawlessly . if I were you I'd try one of two things. Either uninstall magisk and unroot and try again. Or wipe and reflash everything.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] clothednblack:
Maybe the update released today will fix it, just saw a notification for it.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] danw_oz:
Opened app and it asked to install 5.6.0, force closes and causes root to stop working, gone back to 5.5.5. others experience may differ as I am running a custom rom, and an older version of magisk zip.

Update fully flashed 15.4 and all is working fine now
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] clothednblack:
No idea, I'm on DU rom and 5.5.5 with 15.3. No root issues or mods disappearing after reboot
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] CyberpodS2:
All good here.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] dricacho:
I'm a little perplexed about this. I just flashed v15.4 in TWRP. After rebooting the phone to check SafetyNet, it shows this. I thought v15.4 is the latest version over 15.3.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] pkgnex:
That happens if your Update Channel in the settings is "stable" and you have flashed a beta through recovery. 15.3 is the latest stable... and I'm guessing you manually flashed 15.4 through recovery?
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Az Biker:
I noticed the same thing and said something in the "DU is here" thread, as it only happened after flashing DU. Maybe I should've said something here too.

Haven't noticed anything weird other than the mismatched versions.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] chazall1:
Same exact issue and I am on stock. I no issues and all functioning as expected.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] danw_oz:
Whats wrong with that? it says your running 15.4 which is a beta version, the other version mentioned is latest stable/released version.

Sorry replied to the wrong person, and see you are saying pretty much the same thing
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] purenrg13:
I have attempted to root with magisk multiple times. A gone 20attempts in 1 night. I thought that I may have been doing something wrong. Bootloader is unlocked. I went to Google to download the pixel 2xl tiamut 8.1.1 image.

When it is transferred to magisk manager on the phone it finds it and patches it with no issue. Or so I can Guess. However, once it is sent back to computer and put into the command prompt with the code, it tells me image is corrupt. What would cause this?

Please let me know if there is another reliable place to get boot images.

Or if there is a step missing that it making the file corrupt.

Any help with this matter would be great.
[Google Pixel 2 XL ROMs, Kernels, Recoveries, & Oth] Az Biker:
Unless that's a typo, I didn't see a Taimen 8.1.1 factory image on the Google page.

These are the steps I follow, maybe look through them and see if you're missing or skipping a step.

Download the Magisk 15.4.zip file, and flash it in TWRP, it will automatically install magisk manager.