Nighthawk App no longer functioning

Hi, 

I received an email last week from Netgear Security that new firmware was available, however, the Nighthawk app on my IPhone keeps saying that it either cannot find the router or that WiFi is not detected, yet all our devices are connected to the router. (Note: I just switched from Iphone 6 to Iphone SE; the app was working fine until recently so I'm not sure if there's an issue with the new phone).

I've followed the troubleshooting advice from the app itself. I've also deleted and re-installed the app; I've rebooted the router too. I also tried accessing the router via its IP address or routerlogin.net but no luck. I also tried different browsers. And I tried searching the community for something relevant.

I spoke with a support rep last Thursday but he couldn't isolate the issue. During the call, he checked with his colleagues who advised him that there were no issues with the app. I stopped short of giving him remote access to my laptop as I wasn't confortable with that.

I was hoping someone may have some advice or point me in the right direction to solve this issue.  

Thanks!