How do I stop my SIM card from auto-locking while powered on?

I have a set a SIM PIN on the SIM card I use in my Moto E4 Android phone. To answer some anticipated questions in advance:

• I know my PIN
• I want the SIM to lock when the system powers down or reboots
• I want to have to enter the PIN when the system first powers up
• All of the above are working fine for me

What I do not want is for the SIM to lock itself while the phone is powered on. I don’t know how long it takes, but it seems like if I do not use the phone for an hour, when I try to use it, the SIM is locked again and I have to enter the PIN to unlock it. I suspect this means I cannot receive incoming calls for some period of time because the SIM card is locked.

I know the phone is not rebooting because after I unlock the SIM, I can still unlock the phone with my fingerprint. When the phone reboots, I have to enter my passcode.

I do not know much about Android, this is my first Android phone and I just have it as a backup. Is this auto-lock a feature I need to disable? It seems to me like a bad idea given that I want to be able to keep receiving calls. What can I do to fix this?