If you are HN you know how to RTFM, I guess.

The Fix: Lock it Down:

Go to Settings > Screen Time.

Tap Turn On Screen Time (if not already on) and set it up for your child.

Tap Use Screen Time Passcode and create a passcode that the child doesn't know.

Go to Content & Privacy Restrictions (under Screen Time) and turn it on.

Tap Allowed Apps (to disable camera/other apps if needed) and Change Restrictions.

Under Content & Privacy Restrictions, find Date & Time Changes and set it to Don't Allow Changes or Require Password.