As for bad cellular reception after an update? "If not in a usual zone where it worked for you before" it might be update bug.
I had a similar problem today after updating to Android 13 on an S21. A group text kept prompting that a message was awaiting download and that data service was needed. My cellular status icon did not indicate 4GLTE or 5G. My cellular connection was not connected to data services. I went to Connections/SIM manager and turned off the Verizon SIM and turned it back on. I then got a 5G connection and subsequent group texts came through without issue.