yashsingh1/xdaforums huggingface dataset:
[OnePlus 5T  Guides, News, & Discussion] MintyTrebor:
Thanks Andrew. I glad you confirmed it was working.

I checked all those settings, and confirm my device shows the same information, even in the phone information screen. I'm just not seeing the VoLTE icon (yes I checked the icon was enabled!!)...

I'm running stock OOS (latest), with Magisk and Viper4Android module, which are the only changes I have made...I am wondering if rooted/unlocked has any negative effect??

I have an s7 edge @ home, which works with 3's VoLTE, so I will also double check the sim still has VoLTE activated when I get back from sunny Glasgow.

Thanks Again
[OnePlus 5T  Guides, News, & Discussion] pcm2008:
Thanks!

Can confirm that VoLTE/ViLTE and VoWiFi/ViWiFi are fully functional on MTS Russia with India_VoLTE_Vodafone profile.
[OnePlus 5T  Guides, News, & Discussion] AmazingHorse:
Worked fine on OP5 OB14. Had to disable xXx Magisk module and got crashes when i clicked on Serial. Dunno why but *#808# fixed that and i found my phone in PDC.

Russia, Moscow, MTS. VoWifi is not working, but i dont even know how i can check it

Thank you :)
[OnePlus 5T  Guides, News, & Discussion] leopard04:
This tutorial NOT working on Oneplus 3 A3000 Oxygen OS 5.0.4 Latest version

Digi.Mobil Romania

Orange Romania

So this tutorial is avaliable on Oneplus 5/5t and 6 because has integrated in Firmware and Modem these Option Oversea-Commercial_DS Telefonica_UK_Commercial

So finaly NO CHANCE of VoLTE and VoWiFi in Romania on OnePlus 3

and on Experience OS OemLogkit is Missing !!!!!!
[OnePlus 5T  Guides, News, & Discussion] neo387:
Confirmed working on Proximus - Belgium

Have to ask proximus to enable it.
[OnePlus 5T  Guides, News, & Discussion] maxx88:
I Confirm, that its working on DIGI Mobil Romania with INDIA Telefonica , both Volte and WoWifi. tested calls on both! thx
[OnePlus 5T  Guides, News, & Discussion] ReNeH99:
Works like a charm for deutsche Telekom Magenta Young contract and telefonica (Oneplus 6, not 5T). Thanks!
[OnePlus 5T  Guides, News, & Discussion] Paz9:
accidentally deleted my EFS backup

is it possibleto somehow restore this to stock? all i did was remove Oversea-Commercial_DS is there a way to bring this back?
[OnePlus 5T  Guides, News, & Discussion] haxelmans:
Try this: https://xdaforums.com/oneplus-5t/how-to/oneplus-5t-unbricking-tool-confirmation-t3733012
[OnePlus 5T  Guides, News, & Discussion] Baptiste94:
[MENTION=4977129]dagoban[/MENTION] Thanks :) would like to report success for VoLTE ( VoWifi doesn't wokr) using these settings :

Country : France

Phone : OnePlus 5T

ROM : OOS 5.1.4

Root : Magisk V16 + VoEnabler1.2

Carrier : B&YOU by Bouygues Telecom

Profile selected in PDC : Commercial-TMO

VoLTE :good:

VoWifi :crying:
[OnePlus 5T  Guides, News, & Discussion] Fabianvk:
It worked for me in Belgium with Proximus using Telefonica_UK_Commercial.

Indeed Proximus must have enabled it on their side.

I'm on OnePlus 5 with OOS 5.1.4.
[OnePlus 5T  Guides, News, & Discussion] gtoussai55:
It seems that VoLTE works perfectly with many PDC profile in France, I tried many of them.

But I can't figure it out how to make VoWiFi working.

You activate both sub0 and sub1 ?

My carrier is SFR.
[OnePlus 5T  Guides, News, & Discussion] haxelmans:
I can also confirm that it works with Proximus Belgium.

Proximus has to enabled it on your number.
[OnePlus 5T  Guides, News, & Discussion] Baptiste94:
I've tried every PDC profile and the one i'm using is the only one that is working on my phone, I might be a little bit unlucky :).

I did activate Sub0 and Sub1 even tho I only use the 1st SIM slot, does it make any differences ?

Someone on the thread said that he solved his VoWifi issues by changing the DNS from Google to Cloudflare in his router : Here

Unfortunately I can't try it, my router doesn't let me change DNS :crying:
[OnePlus 5T  Guides, News, & Discussion] superzell:
VoLTE worked for me too with Commercial-TMO.

Still no VoWifi (I tried changing my DNS servers)

French carrier : Bouygues Telecom
[OnePlus 5T  Guides, News, & Discussion] gtoussai55:
Ok thanks but the DNS1 of my Freebox V6 is already 1.1.1.1 and DNS2 is 8.8.8.8

I have tested on a Livebox with the regular DNS but no VoWiFi too.

I activate the VoLTE on the OnePlus 5 of my sister :

Carrier : Bouygues Telecom

PDC profile : VoLTE OEM Lab (sub0 and sub1 activated)

But no VoWiFi.

On my OnePlus 6 on SFR : PDC profile that work for VoLTE but not for VoWiFi (non-exhaustive list)

- VoLTE OEM Lab

- VoLTE OEM PTCRB

- India VoLTE Vodafone

I think I will check every profiles to test the VoWiFi.

I will post my results.
[OnePlus 5T  Guides, News, & Discussion] Huffy1:
For Australian users I've finally tested for you.

Vodafone and Optus work however calls sound exactly the same as 3g when talking to another volte enabled phone which was an iPhone 6s.

Telstra does not work, drops to 3g when making a call

All SIM cards have been Volte provisioned.

As far as I know all MVNO'S (Boost, virgin, Aldi mobile etc) do not support volte, you have to be with one of the big carriers.
[OnePlus 5T  Guides, News, & Discussion] scottysau:
Your the boss. Let us know if you find a fix for Telstra :good:
[OnePlus 5T  Guides, News, & Discussion] Huffy1:
I have been in contact with them and they are very stubborn but told me it's active. Gonna try it on an iPhone. Will keep you updated.
[OnePlus 5T  Guides, News, & Discussion] VoltaGe86:
Huffy1 you did better than me, OnePlus 5t Telstra customer here but cannot get VoLTE or VoWiFi to show on the status bar at all. Tried both Telefonica_UK_Commercial and India-VoLTE-Vodafone profiles.
[OnePlus 5T  Guides, News, & Discussion] thaidroid:
Tried both India and UK profile, both drops to H+ when I make a call so I guess it does not work,

True Thailand is my phone company.
[OnePlus 5T  Guides, News, & Discussion] M.Sami:
Did you need anything other than calling Optus to activate it? They told me it is activated even though I'm on a prepaid plan and I still can't get it to work
[OnePlus 5T  Guides, News, & Discussion] maikvitesse:
Telefonica_UK_Commercial works for KPN in The Netherlands!

I now have VoWiFi and VoLTE

Very happy with this!
[OnePlus 5T  Guides, News, & Discussion] MikeRox:
Works in Germany with Aldi talk.

Doesn't work with T-Mobile prepaid, because it is not supported by the provider. (Prepaid)

BR

Mike

Gesendet von meinem ONEPLUS A5010 mit Tapatalk
[OnePlus 5T  Guides, News, & Discussion] lwkoon:
Try to use the Volte_OEM_Lab it works on U mobile and UniFI on my 2nd SIMs as well, as the India-VoLTE does not work in Umobile VoLTE but works only in UniFI SIM

now both works great but no VoWIFI on U mobile as it is working on iphone.

anyone on U Mobile, Malaysia?
[OnePlus 5T  Guides, News, & Discussion] nealed:
Hello, on my OnePlus 3, I don't have the India-VoLTE-Vodafone or Telefonica_UK_Commercial profiles. Ok. No problem, I can try others.

However, I have a question: I have 2 different SIM cards, one from SFR France, and one from Swisscom, Switzerland.

Assuming that these have different VoLTE profiles - can I apply different profiles on slot0 and slot1 for SIM1 and SIM2?

Currently, VoLTE is working on Swisscom SIM, but not on the SFR SIM.

Any advice?
[OnePlus 5T  Guides, News, & Discussion] n1GGaZ:
Hello this is my config (VoLTE works, VoWifi not tested and have to call carrier to enable VoLTE first):

Country : Bulgaria

Phone : OnePlus 6

ROM : Android P Beta 3

Root : Magisk 16.7 + OnePlus_2-6_OOS-OB_VoLTE-VoWiFi_Enabler_v1.0

Carrier : Telenor

Profile selected: India-VoLTE-Vodafone
[OnePlus 5T  Guides, News, & Discussion] godzifa:
Hello,

This is my config (VoWifi works (most important for me), VoLTE dosnn't work (I called my carrier but they don't know what I'm talking about...)) :

Country : Switzerland

Phone : OnePlus 5

ROM : OxygenOS 5.1.4

Root : none

Carrier : Salt

Profile selected: India-VoLTE-Vodafone
[OnePlus 5T  Guides, News, & Discussion] captainpuppet:
Hi!

I didn't make a backup of my efs partition. And I removed the line "Oversea-Commercial_DS". Is there any way to retrieve it?

Was it important? Now I have activated "Telefonica_UK_Commercial" and the phone works just fine, but could I have problems in future?

Thanks
[OnePlus 5T  Guides, News, & Discussion] Huffy1:
Unfortunately does not work with Telstra Australia. Tested the Sim card in an iPhone and volte works fine however does not work on the OnePlus.

Shame cause it works fine with Vodafone Australia.
[OnePlus 5T  Guides, News, & Discussion] alexchandra:
Works for me! Thanks!

Country : Indonesia

Phone : OnePlus 5

ROM : OxygenOS 5.1.4

Root : Magisk 16.7 (using VoEnabler Magisk Module)

Carrier : Smartfren

Profile selected: India-VoLTE-Vodafone
[OnePlus 5T  Guides, News, & Discussion] celbey:
Confirmed.

Telefonica_UK_Commercial works for TURKCELL in The TURKEY!

I just followed to HOWTO and voila VOLTE and VOWIFI both are working.

Thanks,
[OnePlus 5T  Guides, News, & Discussion] vkass:
VoLTE icon shows up with Bell Canada but calls won't connect, if I disable VoLTE in settings it connects by switching to 3g.

Looks like bell are blocking it on their end.

Edt:

Rebooted again and it works!

Using ATT profile, after every reboot need to disable and enable VoLTE in settings.
[OnePlus 5T  Guides, News, & Discussion] fyah_:
Hello,

I am not sure about the link between profile slot & sim card slot.

I have oneplus 3 & SFR, VoLTE working with multiple profiles, currently the test lab.

maybe you can find one profile that works for both..

Br
[OnePlus 5T  Guides, News, & Discussion] fyah_:
Hi,

since activating the VoLTE with this method it seems my oneplus 3 power off/reboot randomly in my pocket.

after one or two reboots, the volte is gone and I need to redo the steps for it to come back

does this happen to anyone ?
[OnePlus 5T  Guides, News, & Discussion] vkass:
Aaaaaand they blocked it.
[OnePlus 5T  Guides, News, & Discussion] gtoussai55:
Hey. I am also on SFR and I tested many profiles and VoLTE works perfectly.

But no VoWiFi, I have tested all profile. So I contact OnePlus by chat, they told me they are actually testing VoLTE in France with the carrier and it will be activating with OTA update. That's to say they will add a custom profile for French carriers since no profile activate VoWiFi.

Maybe available with the Android P update !? Can't wait !
[OnePlus 5T  Guides, News, & Discussion] HC4Life:
Any video showing the steps?
[OnePlus 5T  Guides, News, & Discussion] HC4Life:
Can someone tell me how to do this?

What is "PDC" and QPST on step 5? I'm confuse :confused:
[OnePlus 5T  Guides, News, & Discussion] fyah_:
These are the qualcom programs installed on your pc.

Search for the "software download" application and run as admin
[OnePlus 5T  Guides, News, & Discussion] sensitd:
I have a OnePlus 3.

Until point 4 no problem. I have the possibility to activate VoLTE and VoWifi in my settings

5) Open "PDC" in your QPST start menu folder, best to do by right click & "run as administrator"

Select your device, right click on "Oversea-Commercial_DS" and deactivate Sub0 and Sub1

Click on Oversea-Commercial_DS again and click on remove

(I don't have Oversea-Commercial_DS but I have OEM_Overseas-CDMA-Commercial which is the only active so I guess it's the one we're talking about)​

6) Close the app and reopen it

Reopen witch app ? PDC ?​

7)Select India-VoLTE-Vodafone or Telefonica_UK_Commercial, right click and SetSelectedConfig for both Sub0 and Sub1

Where can i find these profils?​

8)Click on the profile from step 7 again and click on Activate

Yes, select UK/India even if you are located in another region (see above for comfirmed locations + carriers)

9) Restart your phone

Thanks in advance for your help.

For those who have a OnePlus 3 which profile do you activate for VoWIFI?​

Success for VoLTE but not for VoWifi
[OnePlus 5T  Guides, News, & Discussion] swa100:
Did you try the other method?
[OnePlus 5T  Guides, News, & Discussion] fyah_:
Hi,

see attachment, VoLTE on SFR works with OEM_Test_Card_Lab and OpenMkt-Commercial-CU

Br,
[OnePlus 5T  Guides, News, & Discussion] vache:
Working fine here on French carrier SFR after selecting Telefonica_UK one. (OP6)
[OnePlus 5T  Guides, News, & Discussion] scottysau:
Telstra are blocking it. I had a argument with them and told them they were deliberately been selective for marketing reasons. Raised an official complaint that I could take to the ombudsman but can't be bothered. Maybe I should of and we would get full support like German carrier's.
[OnePlus 5T  Guides, News, & Discussion] grootooter:
Is this modification surviving update to 5.1.5 (op 5T)? If not, can it still be applied?
[OnePlus 5T  Guides, News, & Discussion] haxelmans:
it survives :)
[OnePlus 5T  Guides, News, & Discussion] abogrhen:
this actually working on

zain- ksa using India-VoLTE-Vodafone

but not on stc -ksa
[OnePlus 5T  Guides, News, & Discussion] mnurolcay:
No problem after updating from 5.1.4 to 5.1.5 with Oxygen Updater. The trick still works.
[OnePlus 5T  Guides, News, & Discussion] Sefko:
On Orange Slovakia, VoLTE or VoWiFi does not work. I tested Telefonica UK, India_VoLTE_Vodafone and other, but not working :( I'm using One Plus 5T + Oxygen 5.1.5
[OnePlus 5T  Guides, News, & Discussion] Stilleh:
Any chance you can try this with Tele2 in Sweden?
[OnePlus 5T  Guides, News, & Discussion] jordirpz:
Hi, when I enter * # 801 # in the phone application, nothing happens.

oneplus5 OB15
[OnePlus 5T  Guides, News, & Discussion] acemimerakli:
Did you try other options?
[OnePlus 5T  Guides, News, & Discussion] ds22:
Does also work without it, or is it absolutely necessary?
[OnePlus 5T  Guides, News, & Discussion] Sefko:
Yes, I tested about 8-10 other possibilities and did not working... I also got root of One Plus 5T, it did not help. I also contacted my operator Orange Slovakia and I covered 4G, as well as on the my SIM card is VoLTE enabled ..
[OnePlus 5T  Guides, News, & Discussion] maikvitesse:
Without following the steps in this guide it doesn't work. So yes it is necessary until KPN or any other provider supports OnePlus phones.
[OnePlus 5T  Guides, News, & Discussion] astracd:
Must be OP dialer not Google or some other.
[OnePlus 5T  Guides, News, & Discussion] jordirpz:
please, where is OP dialer?
[OnePlus 5T  Guides, News, & Discussion] vipsms:
For Ooredoo-Kuwait:

I applied India-VoLTE-Vodafone profile

VoLTE worked only.. but VoWifi doesn't.

Thanks alot dagoban ?????

---------- Post added at 10:46 AM ---------- Previous post was at 10:44 AM ----------

OP dialer = Oneplus dialer

It is the stock usual phone dialer in oxygen os rom. Don't use the google/aosp dialer
[OnePlus 5T  Guides, News, & Discussion] jordirpz:
Lol, thank you.

I used op dialer.

Well, i did debloater the ob15, maybe the problem
[OnePlus 5T  Guides, News, & Discussion] johnstinks:
hi,

someone have found to make it work on Orange France ?

i've tried and nothing seem to be working
[OnePlus 5T  Guides, News, & Discussion] ingamedeo:
Works with TIM, Italy (Telecom Italia Mobile)
[OnePlus 5T  Guides, News, & Discussion] etecka:
O2 Czechia works with Telefonika UK settings. Thanks!
[OnePlus 5T  Guides, News, & Discussion] captainpuppet:
Hi! Do you see voLTE icon on the status bar? Or just in the menu of the phone?

I am with Vodafone, and though I can see and enable voLTE from the menu, in the networks menu, I can't get it to work.
[OnePlus 5T  Guides, News, & Discussion] ingamedeo:
I do.. The icon is there and VoLTE works, tried calling and it doesn't switch to 3G.

Try with the Vodafone-India config from the link above, also ask Vodafone to enable Voice HD on your SIM card.
[OnePlus 5T  Guides, News, & Discussion] ds22:
Bit the bullet and enabled it on my OnePlus 6, and I'm glad that I did. :D

One question though.

Will this mod persist after an OTA update?
[OnePlus 5T  Guides, News, & Discussion] ingamedeo:
Yes. This mod tweaks the content of the EFS partition, it should survive OTAs..
[OnePlus 5T  Guides, News, & Discussion] Bofahad:
I confirm this way not working on OnePlus 6 5.1.11 (Kuwait , VIVA )
[OnePlus 5T  Guides, News, & Discussion] T.Souza:
I have a OnePlus 3.

5) Open "PDC" in your QPST start menu folder, best to do by right click & "run as administrator"

Select your device, right click on "Oversea-Commercial_DS" and deactivate Sub0 and Sub1.

I don't have Oversea-Commercial_DS but I have OEM_Overseas-CDMA-Commercial (single active), would that be for op3?

And I did not find any program to run the second tutorial that is with the "Software download" program the closest I found is eMMC software download.
[OnePlus 5T  Guides, News, & Discussion] fyah_:
Yes this is correct for both
[OnePlus 5T  Guides, News, & Discussion] :
Delete
[OnePlus 5T  Guides, News, & Discussion] Adnan008:
TURKEY Vodafone and TURKCELL works with india-volte-vodafone, both vowifi and volte, you can add to the list.

you need to send an sms from a supporting phone to activate volte on that simcard for turkcell to work at first, but then it works fine.
[OnePlus 5T  Guides, News, & Discussion] mnurolcay:
It works actually for Turkcell, too. Check this post

https://xdaforums.com/oneplus-5t/ho...n-carriers-t3817542/post77174423#post77174423
[OnePlus 5T  Guides, News, & Discussion] Adnan008:
thanks for the info! i thought of this and im gonna try this about in an hour, will try both uk and india, and post the results.

turkcell is very strange tho, i also have huawei p20 lite, when i put vodafone, volte and vowifi worked from the start, but turkcell don't recognise huawei, it only supports a few lg, samsung, 2 local company, and iphones..

edit: it worked!
[OnePlus 5T  Guides, News, & Discussion] swa100:
What's the easiest way to revert back to original configuration when needed when not-rooted? Wanted to know before trying, just in case ;)
[OnePlus 5T  Guides, News, & Discussion] Blackz Afiqz:
I cant get volte if i choose lte only lol
[OnePlus 5T  Guides, News, & Discussion] godzifa:
If you have an OP5 (and only an OnePlus 5): https://xdaforums.com/oneplus-5/how-to/firmware-modem-collection-flashable-zips-t3627049
[OnePlus 5T  Guides, News, & Discussion] fourcc:
I can't reach the menu after "*#801#" to switch on "Serial" and "Full-port switch". It always directly jump to this attached screen.. Is this because I have a custom Rom such as No limits?

I can confirm this was the reason. To fix it I disabled the Rom in Magisk, I rebooted and the my device recognized the *#801# dial code and I was able to switch on "Serial" and "Full-port switch". Rebooted and then PDC recognized my device and follow the next steps. After I final reboot. I got VoLTE and VoWifi working. Then i re-enable again Nolimits custom Rom and everything is working.! Great!
[OnePlus 5T  Guides, News, & Discussion] mjemec:
OP 3T here. I don't see the option 7)

Select India-VoLTE-Vodafone or Telefonica_UK_Commercial, right click and SetSelectedConfig for both Sub0 and Sub1

edit: Got it working using multiple suggestions in this thread. You can add Telekom Slovenije (Slovenia) to the list of working carriers.

So for 3T for step 5 disable OEM_Overseas-CDMA-Commercial and for step 7/8 enable OpenMkt-Commercial-CU (OEM_Test_Card_Lab did not work for me).
[OnePlus 5T  Guides, News, & Discussion] vamvakarisn:
Can someone provide direct download links (Step 2) for ONEPLUS 6 please?
[OnePlus 5T  Guides, News, & Discussion] filipebig:
Works on Oneplus 6 ! Vodafone Portugal

Thank you
[OnePlus 5T  Guides, News, & Discussion] adrian.l88:
I can confirm it works with KPN in The Netherlands. :D
[OnePlus 5T  Guides, News, & Discussion] Huigie:
Really... And when you get called you can see who's calling you?

---------- Post added at 05:18 PM ---------- Previous post was at 05:16 PM ----------

Caller ID works? You can see who's calling you?
[OnePlus 5T  Guides, News, & Discussion] ds22:
I can confirm it works on KPN.
[OnePlus 5T  Guides, News, & Discussion] adrian.l88:
I did not activate the No Limits Magisk Module after setting it up so maybe that is the reason why the the caller ID works.

I did have issues with the No Limits Magisk Module or the blu_spark kernel but I do not know yet which was the culprit.
[OnePlus 5T  Guides, News, & Discussion] n0quart3r:
[MENTION=4977129]dagoban[/MENTION] thanks for the guide.

I confirm it works in France for Bouygues Telecom on op5.
[OnePlus 5T  Guides, News, & Discussion] zouzou91300:
Which profile did you use ? VoLTE and WoWifi working ?
[OnePlus 5T  Guides, News, & Discussion] n0quart3r:
Hi.

I used the Telefonica_UK_Commercial as instructed in the first post.

Both VoLTE and Vowifi work.
[OnePlus 5T  Guides, News, & Discussion] zouzou91300:
Ok. Thank you, I will try this on my OP5.
[OnePlus 5T  Guides, News, & Discussion] pister:
Anyone could make it work with Orange Spain?

I tried all the configurations and only worked VoWifi with Telefonica_UK_Commercial but if I disconnect from wifi goes off and when I reconnect, no longer appears. Even if I reboot the phone.
[OnePlus 5T  Guides, News, & Discussion] Blackz Afiqz:
Guys, do you get volte when force lte? my volte gone when I forced LTE only... Can you guys confirm this?
[OnePlus 5T  Guides, News, & Discussion] yochitaro:
Please guide me to do a nandroid backup via fastboot by non rooted.
[OnePlus 5T  Guides, News, & Discussion] fyah_:
Hello,

After several weeks of using VoLTE on Oneplus 3, carrier SFR France, profile Volte_OpenMkt-Commercial-CMCC

I just noticed that calling is not working when dialing fixed numbers. No problem with mobiles

anyone noticed such issue ?
[OnePlus 5T  Guides, News, & Discussion] HC4Life:
My carrier is also Vodafone Portugal, i tried the method and it seems not working for me...i'm running Open Beta 17 rom.

Any help?
[OnePlus 5T  Guides, News, & Discussion] filipebig:
You must go to https://forum.vodafone.pt and talk to Moderador to ativate volte on your number.

Whithout ativate the volte in your number by Vodafone Portugal,the volte dont work.

Abraço
[OnePlus 5T  Guides, News, & Discussion] soxfor:
[MENTION=695508]HC4Life[/MENTION],

Or talk to their support via the online chat, I did it that way. Could be faster than the forum. https://ajudachat.vodafone.pt/?lang=pt
[OnePlus 5T  Guides, News, & Discussion] VoltaGe86:
I'm not having much luck. I've tried the guide and have enabled VoLTE but the logo will not show up on the status bar. My carrier (Telstra in Australia) supports HD calling. I contacted Telstra and they claim VoLTE is enabled. I'm not sure where to go from here.
[OnePlus 5T  Guides, News, & Discussion] fyah_:
Hi,

Tested all available profiles in OP3.

All profiles where VoLTE works results in the same behavior with fixed numbers.

It rings once or twice and hang up.
[OnePlus 5T  Guides, News, & Discussion] mjemec:
After 2 reboots VoLTE is gome for me, no matter what I do.
[OnePlus 5T  Guides, News, & Discussion] victorwalter:
wrong forum, pls delete..
[OnePlus 5T  Guides, News, & Discussion] Sefko:
OK,after contacting my carrier and activating VoLTE and VoWiFi it is functional:good: ... The first operator was probably deaf when I asked about my services activated on the SIM card and assured me of "YES of course..." :D

UPDATE:

VoLTE only worked for about 2 hours, then the status bar icon disappeared ... I repeatedly rebooted, deleted cache + dalvik cache, restored network settings and did not work ... my carrier rejects the connection the LTE network, although the VoLTE service is activated on the SIM card ... VoWiFi also does not work :(
[OnePlus 5T  Guides, News, & Discussion] HC4Life:
Works like a charm after contact the carrier in my case Vodafone Portugal and after reboot phone, the icon VoLTE shows up in status bar, however my carrier doesn't support VoWiFi.

Thx :)
[OnePlus 5T  Guides, News, & Discussion] guide144:
Confirmed - work in Thailand

Have been follow the institution and it work!! I'm using AIS and Line network.
[OnePlus 5T  Guides, News, & Discussion] mo0ody:
Thank YOU

Confirmed working with Zain KUWAIT using UK settings..
[OnePlus 5T  Guides, News, & Discussion] vamvakarisn:
Has anyone installed Android 9 Pie 1st Open Beta?

I wonder if it still works...