I use my MB Air 2020 for my school and other stuff. It has done dis to me twice!
The first time happened on January 31, 2021 on macOS Big Sur 11.1 where the Battery level will display more than 20%, then shut off and wouldn't turn on when unplugged, and then the battery now jumps all the way to 1% and the date and time will show the incorrect date and time, it took me two attempts to log in because the first time, there was no sound on start up, the screen was completely blank after logging in, the second time showed a black screen with keyboard brightness, and after that, it said "You shut down your computer system because of a problem", and dat's when the battery jumped ALL the way to 1% and was showing the incorrect time.
Second Time happened on Friday, April 23, at 9:15 PM when I was trying to help my friend on schoolwork, it restarted on it's own upon waking up. There were no problems logging in, but I was greeted with "Your computer was restarted because of a problem"