Which version of MacOS are you running?
EDIT: besides having the latest version of Big Sur installed, try resetting your system management controller:
- Shut down your Mac.
- Hold down the following keys: Control, Option and right Shift.
- After holding those buttons down for 7 seconds, press and hold the power button.
Resetting the NVRam might help:
- Shut down your Mac.
- Press and hold Option, Command, P and R immediately after turning your Mac back on.
- Release the keys after: two startup sounds or when the Apple logo appears and disappears for the second time.