So i tried the alliance shield method days ago ( att / S21 ultra unlocked ) was able to set the settings where they stayed. But even with the phone popping up advacned messaging tab and Voip calling etc. The features didnt work. I factory reset and went back to my u1 firmware. But I couldnt get google messages to verify my number . ( i did all the troubleshooting - carrier services, fore stop delete data etc ) but no still wouldnt verify.
I decided to take a look into the alliance shield one more time and found a provisioning tab, See attached pic. After hitting enabled. I force stopped Carrier services, Google messages, samsung messages, deleted all storage data when i went throguh each. And was instatnly able to verify my number. No waiting 7 days or any of that nonsense.
Having att. alliance shield would not let me use video calling nor avdvanced messaging even though it was turned on in options or even running U firmware from att. ( NOTE - I hate ATT ) . But this method will at least let you go back to your U1 and be able to verify chat features in google messages. and not have to wait to verify your number. Hope this helps some people out.
in alliance shield goto the IMS settings like you would to enable RCS. I still left all RCS options on.
than scroll down till you see provisioning like in the screenshot. Hit provision. and than go force stop , clear data etc.
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UPDATE --
So I was testing around with it. It seems if you have problems or fiddle a bit it will do the same verifying [Not verify] , ( or if it is already set to enabled )
If you go back in and disable provisioning and reenable that , force stop, clear data. it will verify instantly .
It will now send RCS messages VIA google to another google enabled user properly.
It will also work on the beta google messages ( samsung version from apkmirror )
