[Google Pixel 8 Pro] badabing2003:
You were on Dec. release on slot A, probably (most likely with Magisk hidden) and Magisk 26.3

You created a patch with that version of Magisk

You updated to March release and got rooted on slot B with Magisk 26.3

Selected Device on 2024-03-13 11:45:46:
Device ID: REDACTED
Device Model: husky
Device Active Slot: b
Device Mode: adb
Device Name: Pixel 8 Pro
Device First API Level: 34
Device Version End Date: October 2026
Device Secuity Update End Date: October 2030
Has init_boot partition: True
Device Bootloader Version: ripcurrent-14.4-11322024
Device is Rooted: True
Device Build: AP1A.240305.019.A1
Device API Level: 34
Android Version: 14
Android Name: Android 14
Android Codename: Upside Down Cake
Android Release Date: Q3 2023
Android Latest Update: Present
Device Architecture: arm64-v8a
Device Kernel: Linux localhost 5.15.131-android14-11-gd99d9fe08e0c-ab11209359 #1 SMP PREEMPT Tue Dec 12 17:18:56 UTC 2023 aarch64 Toybox
Device Kernel Version: 5.15
Device KMI: 5.15.131-android14
sys_oem_unlock_allowed:
ro.boot.flash.locked: 0
ro.boot.vbmeta.device_state: unlocked
ro.product.first_api_level: 34
ro.boot.veritymode: enforcing
ro.boot.verifiedbootstate: orange
ro.secure: 1
ro.zygote: zygote64
ro.vendor.product.cpu.abilist: arm64-v8a
ro.vendor.product.cpu.abilist32:
vbmeta type: ab
Slot A Verity: Enabled
Slot A Verification: Enabled
Slot B Verity: Enabled
Slot B Verification: Enabled
Magisk Manager Version: :
Magisk Path: None
Checked for Package: com.topjohnwu.magisk
Magisk Version: 26.3:26300
Magisk Config SHA1: a06ee98ef5ad217934382f8c875dbebbb4ad6853
Magisk Modules:
Pixel Xpert enabled canary-339
ViPER4Android Reverse Engineered enabled v0.6.1
Call Recorder - SKVALEX enabled 2.3.0 (3.6.5) [Update Available]
Systemless Hosts enabled 1.0
Play Integrity Fix enabled v14.5 [Update Available]
vim for Android NDK enabled v9.0.1447
zygisk-detach enabled v1.8 [Update Available]
Zygisk - LSPosed enabled v1.9.2 (7024)

Then you must have done stuff outside of PF instlled Magisk 27.0, updated root to 27.0

Because at 12:37, it shows that.

Selected Device on 2024-03-13 12:37:22:
Device ID: REDACTED
Device Model: husky
Device Active Slot: b
Device Mode: adb
Device Name: Pixel 8 Pro
Device First API Level: 34
Device Version End Date: October 2026
Device Secuity Update End Date: October 2030
Has init_boot partition: True
Device Bootloader Version: ripcurrent-14.4-11322024
Device is Rooted: True
Device Build: AP1A.240305.019.A1
Device API Level: 34
Android Version: 14
Android Name: Android 14
Android Codename: Upside Down Cake
Android Release Date: Q3 2023
Android Latest Update: Present
Device Architecture: arm64-v8a
Device Kernel: Linux localhost 5.15.131-android14-11-gd99d9fe08e0c-ab11209359 #1 SMP PREEMPT Tue Dec 12 17:18:56 UTC 2023 aarch64 Toybox
Device Kernel Version: 5.15
Device KMI: 5.15.131-android14
sys_oem_unlock_allowed: 1
ro.boot.flash.locked: 1
ro.boot.vbmeta.device_state: locked
ro.product.first_api_level: 34
ro.boot.veritymode: enforcing
ro.boot.verifiedbootstate: green
ro.secure: 1
ro.zygote: zygote64
ro.vendor.product.cpu.abilist: arm64-v8a
ro.vendor.product.cpu.abilist32:
vbmeta type: ab
Slot A Verity: Enabled
Slot A Verification: Enabled
Slot B Verity: Enabled
Slot B Verification: Enabled
Magisk Manager Version: 27.0:27000
Magisk Path: /data/app/~~ihW3Wvcp-3x1LPhDOhAw7Q==/com.topjohnwu.magisk-kLqWmXZuT_cpfxNURT82vg==/base.apk
Checked for Package: com.topjohnwu.magisk
Magisk Version: 27.0:27000
Magisk Config SHA1: a06ee98ef5ad217934382f8c875dbebbb4ad6853
Magisk Modules:
Pixel Xpert enabled canary-339
ViPER4Android Reverse Engineered enabled v0.6.1
Call Recorder - SKVALEX enabled 2.3.0 (3.6.6)
Systemless Hosts enabled 1.0
Play Integrity Fix enabled v15.9.4
vim for Android NDK enabled v9.0.1447
zygisk-detach enabled v1.13.0
Zygisk - LSPosed enabled v1.9.2 (7024)

You're suffering from Magisk multiple identity crisis :)

Run TB checker from playstore, it should find your hidden Magisk and tell you the package name.

Uninstall all that it finds

reboot

Install Magisk 27 again

Run it and enable Zygisk if it isn't already.

You should be fine.

PS: some of your modules might not work on 27, make sure you test them and update them.