Hello! Error code 2 means that you are not authorised in Family Control or device is under control of adult account. you have to use real device with apple’s child account

Thanks for your respond! But the biggest problem I faced is that DeviceActivityMonitor extension doesn't work. I completely don't know why. Only if I run it from Xcode it works, but if I run the simple app - it doesn't do anything. At least in Xcode 13.1

Seems like example in link don't work (Xcode 13)