When you completely discharge a MacBook with an M1 processor and the device runs out of power, it will lose the date and time on the next boot.

Normally there is a backup battery on a mainboard, which keeps the time and date in such a case. I cannot yet say what Apple has done here exactly and why the problem occurs. But I have a solution for you.

I recently faced the same problem and tried to set the Mac to automatic date and time setting via System Preferences > Date & Time.