After the screen is locked for a period of time, unlocking with a password sometimes leads back to the user login screen (the previous user session has been terminated)

[Aravisian]

Another thread recently said the same:

Logged out after computer wakes up from sleep mode and putting in password

I actually wonder if the 6.5 kernel is too new for this chipset. In terminal, does apt search linux-image-5.15.0-83-generic yield results? If it does, you can install with sudo apt install linux-image-5.15.0-83-generic linux-headers-5.15.0-83-generic linux-modules-5.15.0-83-generic linux-modules-extra-5.15.0-83-generi When booting, if needed tap esc or tab to pull up the Grub Menu and select Advanced Options for Zorin and then select Zorin on 5.15.0-83 to boot from and test.

I have seen this before with Nvidia... But they have only Intel - you have AMD. Both Intel and AMD drivers are included in the kernel.