FritzBox TR064 Binding: active remains 1 after device is disconnected


I have a problem with the FritzBox TR064 Binding and my FritzBox 7390 (OS: 06.51).

The web service returns newActive 1 although I disabled the wifi for my Android device, If I take a look at the FritzBox UI the device is marked as an “Active connection”. Any idea what might be the reason?

Kind regards

Edit: Sometimes the state is updated immediately.