I’m having the exact same issue. Tried everything as below users as well and it’s not fixed.

In an attempt to fix this issue i did a full restore and not even 5 minutes after the restore finished i lost all cellular and network again. Only way to fix it is via restart unfortunately. I started counting and so far today i had to restart 5 times. Hopefully the engineers know about this issue as i feel it’s not common but at the same time very frustrating to the people who have.