FamilyControlsError error 4.

Hello, I have created a test project and when requesting authorization with this code from the video:

AuthorizationCenter.shared.requestAuthorization { result in
            switch result {
            case .success():
                print("Authorization granted")
                self.startMonitoring()
                return
            case .failure(let error):
                print(error.localizedDescription)
            }
}

I get:

The operation couldn’t be completed. (FamilyControls.FamilyControlsError error 4.)

I am running the project on a physical device with iOS 15 beta 2 signed in with a child iCloud account.

When running:

print(AuthorizationCenter.shared.authorizationStatus)

I get:

Not Determined

What does FamilyControlsError error 4. mean? Why am I not able to get the dialog to grant authorization?