I have exactly the same issue - iPhone ll Pro Max, T-Mobile, e-sim
All iOS 13 betas
I resolved this issue by doing a DFU and wiping the phone completely. After the next update (to 13.3.1 GM) my phone continued to function normally.
....Crossing my fingers this doesnt happen again with the new 13.4 release today.
After updating to iOS 13.4 Beta, I cannot receive any calls, I cannot dial out, the Phone App crashes, the Contacts App crashes, the FaceTime App crashes, and the Settings App crashes upon selecting certain menu items related to Phone, Cellular etc... and the Messages App crashes intermittently. Rolling back to 13.3.1 fixes the problems, but I am not able to restore to my last 13.4 back up. Reported all the bugs to Apple but of course no action yet...
Anyone facing these issues? Any advice?