Undo child restrictions using the childs iphone

I have an Apple-ID but no apple device myself. Did set up the childs iphone with limitations, but now it is impossible to download apps because I do not receive any requests as I myself do not have any apple device. I have tried to reset the phone and turning buying apps etc to Allow without anything changing. When I try to download an app, it still needs a confirmation from the parent. What can I do to undo this or the whole child setting (and rather use Family link)?