The app links to the virtual mobile device on on the hub via the DNI and this is remembered either on the cloud server or on Android I think it is a hardware UUID. I have found that even after deleting the app it may persist in linking to the virtual device (which is usually a good thing).
Do what @bobbyD suggested above first (make sure app is updated)
And also try this: (coming soon to iOS app)
This refreshes the token and reconnects the app to the hubs virtual device.
Last resort more complicated fix:
What may fix it is letting the app create a new "device" on your hub. In order to force the app to ask you to pick a new device (or create a new one) you may need to edit the DNI of the existing one (on the hub side). Just add something like _OLD to the end of it. Once that is done do the "switch hubs" routine on the Mobile app and it should ask you to select a device, DO NOT select the existing device, have the app create a new one. Once that is done, on the hub use Settings > Swap Apps to swap your apps from the old to the new device.
Once you are satisfied this has fixed it, you can delete the old device from the hub.
(verify it has the _OLD DNI so you don't delete the wrong one)
