iPhone 12 Pro Max Hard Reboot Issue

My phone keeps hard rebooting by itself I have discovered the exact sequence of events that cause it to do a hard reboot. When my phone is connected to my home Wi-Fi and connected to my car with CarPlay and I begin to leave my home, just when it looses Wi-Fi and switches to cellular the phone goes dark and the apple logo appears. 

My phone is running the 14.7 beta 3, but this seems to be an issue also with 14.6 public release because my wife’s phone is doing the same thing and she is running 14.6. 

This was removed from the general discussion because the word Beta is in it, this is clearly nothing to do with the beta software as it’s doing the same thing running 14.6

Anyone else having the same issue or knows of a fix?