Did you (on the Android devices) FORGET the WiFi connection that fails and try again by making a new connection?
Is the AC1200 Router Firmware current?
I have a Netgear ac 1200 Router. I have various devices connected to the internet with no issues such as a laptop, 2 cell phones, 2 tablets and a Ring Wired camera. However I have 5 Stuart Cams (Minion Cameras) all of which were connected via wi-fi but over a period of a few months when I have lost the internet due to weather issues one of more would not reconnect to the internet and I get the "Connected, No Internet" error msg. I have rebooted the modem, waited and rebooted the router to no avail. I have even deleted the cameras and re installed them but still get the same error msg when trying to connect to the internet. Again the problem is only with the Stuart Cams; everything else reconnects when internet comes back up. As you can imagine this is very frustrating, Please help.

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