MacBook won't accept admin password

My password is working to log into the computer, but no longer working to unlock admin items. I tried the Command + R recovery and following the instructions here: https://discussions.apple.com/thread/8304968, which no longer seem to apply. Neither of them fixed the issue.

I'm the only user on the computer. I upgraded to Big Sur yesterday, which seems to be when the issue started - TouchID stopped working as well.

Any help would be appreciated.