Amazon WiFi conundrum

[bassey1976iom]

I have a weird one. My router is connected to the vdsl2 connection. All looks fine. WiFi is setup and various devices connected. Also have an Xbox connected over Ethernet. The XBox, my phone and various PCs all say there is no internet connection. An Amazon echo and an Amazon Fire tablet are both working no problem. If I turn the WiFi off, they stop. So they are connected through my WiFi. But every other device in the house insists the connection is down. How?

 

[bassey1976iom]

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  Never got to the bottom of this but a factory reset of the modem followed by a setup from scratch fixed it. Always a last resort as my provider isn't one of the ones in the "select from this dropdown" list so I have to get a lot of settings spot on and, of course, I have no internet to help me whilst I'm doing it!