Yes, fully understanding this is about cell connectivity. Works perfect on WiFi (except at a relative’s house where the WiFi is as bad as dial up) and model 3 Bluetooth phone as key is fine. I could have written many of the posts in this thread. Noticed the problem late July. Did the log out/in, delete and reinstall app back then. That didn’t fix it.
I mostly live on WiFi so I didn’t stay on top of whether I still had the problem. This past week, though, I had several instances of it not working. But I also have some instances of it does work on cell coverage. Like today, I can’t get it to fail when I want to further explore fixes.
I have an iPhone 11. One difference for me is that I don’t have AT$T, but cheapo Cricket which is owned by AT&T and uses AT&T towers. So there is a chance that I have a different permutation of the same problem. Was the end consensus that the fault was totally with AT&T?