When your child's iOS device is in the curfew period or when you trigger Instant Lock, Norton Family hides the installed apps that are installed from App Store including Norton Family and a few of the default apps.
Unlike on Android, it does not entirely lock your child's iOS device. Once the curfew ends or when you unlock the device, your child gets back all the hidden installed apps along with the Norton Family app.
The apps may get rearranged alphabetically. Inform your child that this behavior is usual and none of their apps are removed. Also, recommend your child to not use folders to group their apps.

This problem can happen due to some network issues. To resolve this issue, do the following:

If you think that your child can access the blocked content, then ensure the following:

• You have set up certain features on your child's iOS device to get the best from Norton Family. For more information, read Set up Norton Family on your child's iPhone or iPad.
• You have set the restriction level based on your child's age.
• The child did not tamper with any of the settings that are required for Norton Family supervision.
  You can use the Norton website or Norton Family app for parents to view such activities of your child. If you use an Android device, you can enable parental app notifications to get instant alerts on time supervision and tampering activities.
• The child uses only the Norton Family browser for their online activities.
• The house rule is turned on and configured with the necessary settings.

You may face this issue if you already have a profile installed on the device. For more information and solution, read Fix profile installation issues.