Network map not working on Genie iOS app

This seems to be a constant problem for many users and I can see I’m not unique in experiencing this

Genie app on iPhone has stopped showing connected devices

Logging into router via browser is showing all the devices and allows me to pause / allow internet access but this is hardly convenient for when I’m not in front of my desktop or away from home
I’m running latest firmware and this hasn’t changed since Genie was working last night and has stopped working this morning
I’ve deleted app, reinstalled
Switched phone off and done the same again
Deleted app, switched phone off/on and reinstalled
Rebooted router

All to no effect

Why is this happening so often?
Why is there no answer on any of the threads?