The screen time is also called Parental restriction on the iOS version before iOS 12. And in iOS 12 and iOS 13, the screen time passcode can be easy to remove or change. If you forgot the screen time passcode, you can update the iOS version to iOS 13.4 or above to use Apple ID recovery to change the passcode. For iOS 12 users, they can use iPhone passcode Genius to remove the screen time restriction.