Safari and App Store are available in Lock mode

The issue is possible on iOS devices that run iOS 13 and higher. To be able to lock Safari and App Store, we suggest activating Advanced Features which are a part of the Premium plan. After activating the Advanced Features, the above-mentioned apps will be locked in Lock mode. You'll also be able to lock all apps individually in Child mode as well as allow apps in all modes.

You can find the installation process here:

How to set up the Advanced Features