Just got the tmobile android 12 update on my Oneplus 9pro global version and its causing issues

I just updated my global version too thank got most things are fine but I lost the wifi calling option. Any help?

12 itself for the carrier variants has been a bit of a nightmare across the board..

WiFi Calling for T-Mobile on Android 12, regardless of whether you use the Global/NA, EU, or T-Mobile firmware, does not work.  A number of devices, including Pixels are experiencing the same issues with WiFi Calling with Android 12.  It is one of the many Android 12 issues that are going to be a problem well into the Android 13 release cycle.  

If you need WiFi Calling, like I do or just want your device to remain on a reliable firmware.  Use the MSM Tool for your device to roll it back.  This isn't an easy process but excellent walk-throughs can be found on the XDA-Developers forums for this.  Once you roll back, which will completely wipe your device, so back it up if you value anything on it.  Enable Developer Options and turn off Automatically Install System Updates.  You will still get the annoying prompt for the update, which you can force close the system update app to get rid of until you reboot your device.  

Yeah my bootloader is relocked. And everything working great on 11. Used MSM since my recovery was destroyed when I turned on dynamic updates. Just want to state that everything was stock on my phone other then having an unlocked bootloader. I was kind of hoping that there would be a way to flash the tmobile 12 firmware and modem files onto my global version without losing wifi calling and 5g. But if wifi calling doesn't even work on the tmobile variant ill wait and see if someone comes up with a fix. I'm Kind of a shocked that 12 is so bad with the long wait that tmobile put us through for the release. 

figure it like this..TMO wont give the go ahead to release an update to the OEM until most of the bugs are fixed/taken care of..with how 12 has been rolling out im taking a guess that the previous versions of it were horrible and not deemed worthy of being kicked out...the shocking part would be that THIS variant was the one they gave the ok to kick out lol.

Hi there, would you be able to elaborate or provide a reliable link for this:

Use the MSM Tool for your device to roll it back.  This isn't an easy process but excellent walk-throughs can be found on the XDA-Developers forums for this.  Once you roll back, which will completely wipe your device, so back it up if you value anything on it.  Enable Developer Options and turn off Automatically Install System Updates.  You will still get the annoying prompt for the update, which you can force close the system update app to get rid of until you reboot your device.  

Also, did the roll back completely resolve the issues you were having?  Right now my biggest issues are:

• the silent / vibrate slider no longer works - the notification that it is working comes up but when the phone rings it is always out loud.
• the direct dial and direct message shortcuts are gone and I am not finding a way to re-create them
• calls disconnect as soon as I answer (sometimes two or three times in a row)
• my WiFi seems super slow

Rolling back solved all of my issues.  It's a pain and it sucks, but my device works normally again.

They to to the best of their ability with 5-6 people per model.  Each team is responsible for all regional and carrier variants as well.

Maybe I’ll try the factory reset first after I backup first.

magenta6723572 wrote:

Maybe I’ll try the factory reset first after I backup first.

Some have mentioned a factory reset has solved some minor issues, like Instagram and Facebook apps crashing.  That's about all I have seen a factory reset fix from the 100+ page of complaints on the OnePlus official forums.