iphone 11 Pro - eSim failure - No Sim - Invalid Sim - Blank Cellular Screen

Has anyone had a Sim Failure while using "eSim"?

My phone was working perfectly with eSim (no physical sim) on ATT's network when all of a sudden I started losing all service and receiving "Sim Failure" messages. Where ATT's network is usually shown I now see "No Sim".

I have taken the phone to ATT and in the Cellular tab of settings - I just see a blank screen and no ability to "Add Cellular Network".

When I try to add a new eSim via ATT QR Code my iPhone gives me the following message "Cellular plan can't be set up, eSIM installation is unsupported on your device"

I have done a full erase and resetting of Network settings, a full erase of the entire phone and a restore...all to no avail and still receiving the same "No Sim, Sim Failure"

Pictures attached