Family Sharing - Content Restriction Issue

I have the family sharing set up for my sons iPad. I go in remotely from my iPhone and set the restrictions. I have selected to where website content is restricted adult websites. It keeps getting changed back to unrestricted. He swears he has not changed anything. Nor did I think he could. It has a password on it which I have changed when I thought maybe he found out what it was. But even with the new password it keeps going back to unrestricted. It’s not immediate but it is happening. Anybody else have this problem? I’m not sure where the bug is or why this is happening.