Ring Door Bell Pro

I recntly bought and installed the above, it worked perfectly for a few days then disconnected, since then it wont reconnect, so I deleted it from the app, performed a hard reset, rebooted the router, checked the wifi channels, deleted and then reinstalled the phone app.I put it into set-up mode, scanned the code and then it indicates it cannot connect to the ring network, it does not display at all in the app so no further information, please help?