Screen Time on Child's iPhone - unknown passcode

Screentime has never really functioned properly. When I first set it up a long time ago now I did have control over downtime and apps but had no activity displayed.

At some point I think I set Screentime directly on her iPhone and must have introduced a passcode at that point.

Now the problem is this. I can reset the screen time passcode on my iPhone in the family section. I still get no control at all. But here is the curious thing. The screen time page on her iPhone displays all her activity and options to set downtime etc but when I click on any of those it request a passcode. It is not the same passcode I am setting on my device. So I get the classic time out. There is of course no option to reset this passcode because it is a child's iPhone.

I have made a full factory reset of her phone but the hidden passcode has remained. I suspect this is why I have no control whatsoever from my device but cannot find any way around it at all.

My family sharing page that lists all member also says "Failed to load services" is that helps

We both have an iPhone 8