iPhone X - Not connecting to Wifi extender network

I think this is happening after the 11.2.2 upgrade. My phone has issues connecting to my wifi extender network ( netgear ex2700 ) . Sometimes it shows “ no internet connection” and at other times it shows connected , but in both cases the internet is inaccessible . Other devices ( iOS & android ) are able to connect to this network and work well. My phone is able to connect to my main wifi network and works well without any issues . I checked the wifi extender settings and there are no access control lists preventing this device from connecting . I have also tried to reset network settings on my phone but that hasn’t helped either

Please help !