Pictures not sending via SMS

I switched from Verizon to ATT, but it's been pretty terrible so far. Aside from dropping / horrible call quality (will probably have to buy a booster), picture and videos that my wife never had an issue sending via Verizon, fail constantly with ATT. Maybe 15% make it through.

We are on wireless (tried 4 and 5g), we tried the Samsung Band app to force 4g, we changed messaging apps (went back to Google Messaging after nothing worked), and even did the 'enter your phone number' at a Google site to remove SMS features from previous phones.

No luck. I tried sending 3 pictures from my wife's phone to phone, something that worked 100% of the time previously, and usually quickly.. and after minutes, it still says 'Sending.' Eventually it will probably come up and say Failed.

Any other ideas how to make this work? My wife said she is ready to toss her new phone (S22 Ultra) in the toilet, and I'd like to avoid that.