iPhone app restriction for kids

[aperolspritzbasicbitch]

Hi - posted this in tech but not got any response so thought I'd try here.*
Our year 6 was gifted a phone for Christmas - iPhone 13.
I've set up downtime etc so that the phone can't be used after a certain time, but I also wanted a time restriction on apps.
Originally I set this for 4 hours (obviously not wanting her to have that amount of time usage a day, but new tech, school holidays - figured I'd be lenient to start with)
Supposedly this timer refreshes at midnight, however the time limit is kicking in super quickly, this morning it had kicked in by 9am, she had barely used it - the phone downtime only ended at 7!
Any ideas where I'm going wrong?*

I had the same issue and couldn't figure out why! I ended up using the Qustodio app (the free version). It lets you set time limits easily from your own phone, and I liked that it also allows you to monitor what they are searching and turns on safe search feature. It's very easy to set up but download the app onto your phone first, and then it will give you the name of the children's app to pop onto your dc's phone.