video door bell Elite - worked for 3 weeks now not working

I have a Ring Video Door Bell Elite that is hard-wired to power. It was installed and the app setup and the device worked fine for a few weeks. It has now stopped working.I have deleted and re-added the device to the Ring app and that works.However any action that needs the device to activate does not work, e.g. live view just says 'Activating device' for a minute or so then says 'session ended'. Similarly if I try to set 'Motion Zones'.All the status reports show the device is working find but all I get is as above.