Sign out not available due to restrictions on ipad

This is ridiculous. My son owns an ipad, which I log into with my username/pass to manage. It now says I can't log my son out due to restrictions, so I can no longer log in!?!? Nothing can be done through the apple or icloud websites (which have required me to log in 5 different times, receiving texts on my phones 3 times - not kidding and not due to browser or security settings. - also ridiculous and completely unnecessary if they were to put some thought into their login methods)

Can't update settings -> screentime which is the recommended solution in other similar questions. At a loss as to why Apple is requiring you to buy Apple devices to manage silly settings, and further at a loss as to how I can log him out so I can log in.