MacBook Pro 2021 randomly restarting while in sleep mode in Big Sur

Hello.

This problem just started about a week ago. My MacBook Pro will suddenly shut down and restart when it goes into sleep mode. I get an error message stating it unexpectedly restarted due to an error. I'm on Big Sur 11.6.3.

When I tried to call Apple about it, I was told they couldn't help me unless I upgraded to Monterey - which I don't want to do due to all of the bugs everybody is reporting with Monterey.

... I pay for AppleCare - and found this lack of assistance really mindboggling.

So, I thought I'd come here and see if anyone else has experienced this issue. If so, did anyone find a solution?