parental controls with schedules on iOS

I am trying to use NextDNS parental controls with schedules for my children on iOS.

The issue is that even when using the official DNS profile, children can simply go to:

Settings → General → VPN & Device Management → DNS

and switch from "NextDNS" to "Automatic".

Once this happens, schedules and parental restrictions stop working immediately.

This makes schedules unreliable for parental control use cases.

Is there any recommended way to prevent profile switching, lock DNS profiles, or make parental-control schedules more resilient on iOS?

Currently this feels like a major limitation for families using NextDNS.