Apple Screen Time app limits not working

I’ve used screen time for my kids to limit time on certain apps. It worked well for years, but now I will set the limits and then they will suddenly disappear after a day or even less. Other settings also get erased including downtime and content restrictions. I have changed the passcode and the kids swear they have not tried to change any settings. This issue started about two months ago. I have updated iOS on all the devices. I have turned screen time off and set up settings again. I have tried setting the limits from my device as well as the individual devices. My kids will spend too much time on their phones without limitations in place and creates repeated bouts of anger for my wife. Please help!

[Re-Titled by Moderator]