@inkar.madikyzy That did it! We had been struggling with this for months using Verizon where possible, but we travel to some areas where Verizon doesn’t have coverage, but AT&T does. It would be great if there was a better disclaimer somewhere since this seems to be an issue with a bigger pool of users.
So to be clear, using a data-only plan did not work. Switching to a data+voice plan did work.