Hey there!
Peculiar issue. Sorry, I’m not clear on the issues you’re experiencing. Are you saying that when you enable that preference, close that window, open another app/window, go back, and it’s enabled again?
If that is the case, does the same happen in other preferences? Such as Users and Groups? Or Security and Privacy? Or is it just in one particular presence pane?
Had any other changes happened just prior to this happening? (Such as an environment change/move, an update, a data transfer/migration, etc.)?
Also, can you test to see if the same happens in another user/admin account? (If you could create one just for testing, that would be helpful, as far as isolating a cause).
Likewise, can you start your Mac in safe mode, as another test? If it works fine, this may point to other software installed or a file system issue causing the problem. That would also reveal a lot as far as a possible cause.
Safe Mode:
https://support.apple.com/guide/mac-help/start-up-your-mac-in-safe-mode-mh21245/mac
But, really, if you can say the circumstances leading up to the issue when it started and any particular changes that were made beforehand may be really helpful, cheers!