I get the exact same error when trying to request individual authorisation in the simulator. It does work however when installed on a physical device. I'm hoping apple can fix this so we can test through the simulator.

Hi all, I agree this seems like an oversight. Whoever is the user of the device will have access to the device passcode / face ID. Therefore, being able to turn off the app's Screen Time Access will be possible to whoever is using the device, rendering the restrictions useless. Therefore, I agree it should be the screen time passcode that is used to allow apps to manage restrictions or to remove those restrictions. Have there been any updates on this issue? It's a shame because it means the new individual authorisation functionality with the Screen Time API is fundamentally flawed. Thanks!