I had similar issue, was under Apple Care, they rebuilt the entire phone. At a service center, it was great till Apple care ended, a few months.
Back to the same issue, random reboots and not randomly heats up.
Tried:
Removed protective case.
Turned off all background apps
Turned off app updates/refresh.
Deleted apps.
Do not carry in my pocket.
Bought a new Apple Charger/cord.
Do not use the induction charger any longer.
All this helped but still have the issue it is all random.
Do not expect a lot of help from Apple.
Irony, I traded up from I phone 11 with no issues, to the 14 plus, that was great for a few months.
Good luck!