In that case then it's a hardware reset I'm afraid.
I’ve tried this twice this morning, it seems to be resetting (holding down reset for 5/6 seconds) and then have to set up and adopt via the app, but I’m still getting the same message when I hit on the device.
The help section on UI says it might be as I haven’t forgotten the device on the app, but I can’t because I can’t log in to the device itself and can’t see how/where to do it elsewhere in the app!
Any ideas or suggestions?