IOS 18 Beta glitches

So my phone doesn't have the app store so whenever I need an app my dad has to into screen time settings and unlock it so he can add one. But when he went into content and privacy restrictions and tries to turn it on the little green button doesn't turn and keeps glitching. Because of this I can get no new apps and he can't change any of the content and privacy settings at all. I also cannot find a way to downgrade so it would be really nice if there was a solution to this.

IOS 18 Beta glitches
 
 
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