Hello,
You (the Family Organizer) should be able to adjust the Microsoft Family Safety Screen time limit for your child's account.
To do that, sign in with the Organizer account in the Family Safety settings here:
https://account.microsoft.com/family/home
- Select your child's account and click 'Manage consent'.
- Go to the respective platform for which you want to set screen time: That is, Windows (tab)
- You should be able to adjust the screen time settings for your child's account on the Family Safety webpage.
- To turn limits off, select the MoreVertical icon, then select Turn limits off.
For reference:
Set screen time limits online article for reference.