Unable to Sign Out of my Apple ID on my mac
Some people have solved this by going to System Preferences/Internet Accounts, selecting an iCloud account there, and signing in. You need to repeat this for each iCloud account. Might be a corrupt .plist.

Do a backup, preferably 2 backups on 2 separate drives.
Quit System Preferences.

Go to Finder and select your user/home folder. With that Finder window as the front window, either select Finder/View/Show View options or go command - J.  When the View options opens, check ’Show Library Folder’. That should make your user library folder visible in your user/home folder.  Select Library. Then go to Preferences/com.apple.systempreferences.plist.  Move the .plist to your desktop.

Restart the computer, open the application, and test. If it works okay, delete the plist from the desktop.

If the application is the same, return the .plist to where you got it from, overwriting the newer one.