Mine was working fine after the update then stopped working this morning out of nowhere on T-Mobile. After trying the usual troubleshooting things I went in and turned my SIM off under connections and then back on and it immediately connected and I'm able to use RCS again.
There's a great guide to fixing the RCS chat issues on T-Mobile. First place phone in airplane mode. Go into settings and clear cache and data for "carrier services" as it is a system app. If it's not installed, install it and clear cache and data after airplane mode. Then clear cache and data for Google messages app. Clear phone cache and reboot. Turn off airplane mode and then give it a few minutes and try enabling chat features and it will work. Sometimes it won't if you've tried connecting and reconnecting too many times.
Verified with my S22 ultra that this IMMEDIATELY fixed this issue with mine.*SIDE-NOTE*-Not sure if this helped or hurt me in any way, but for an extra added measure, I did wipe the cache for Carrier Services as well before I tuned sim back on because back on the day it was a part of the dance you had to do to restore chat as well. Good luck!