Motion detection stopped working

HiAbout 6 months ago I bought 4 Ring cameras (1 Elite and 3 stick up cam plug-in) and they have been working fine until Monday when the 3 stick up cam plug-ins all stopped recording motion. There are no more videos appearing in the event history timeline for those 3 cameras either. All 4 are connected to WiFi (Sky broadband in the UK). Interestingly the stick up cam Elite has been unaffected by this.Timeline:Mon 13th April: 2 stick up cams stop recording motion (live view still works)Tue 14th April: the 3rd stick up cam stops recording motion too (live view still works)Stick up cam Elite continues to function fine.I can still do a Live View for all 4 of them but the 3 stick up cam plug-ins simply won't record any motion or send any alerts. When I walk past them the blue light does not go on (I’m sure there was a blue light when it detected motion)..It can't be my wifi as the Elite camera still functions fine and all 4 are connected to the same 2.4 GHz network. All motion settings are enabled including motion verification (the Elite cam works fine, records motion and can send notifications if I enable notifications). I have checked the health of all 3 and they have good WiFi signal and running the latest firmware.Things I have tried:- checked that my router hasn't changed to an unsupported channel by forcing it on to channel 6- checked my device health and the signal strength is good (green)- separated out my 2.4 GHz WiFi channel into a separate SSID to force the cameras to use that- removed the cameras from the app and re-added- factory reset the cameras and re-added- uninstalled the app and reinstalled- disabled all motion settings, and re-enabled- installed the app on another iphone to rule out my iphoneHas anybody had this before ?Is there anything I have NOT tried ? Why would the Stick up cam Elite continue to work but 3 stick up cams have failed ?Eugene