I had this issue but have a different home network setup than most people. I have a Ubiquiti Unifi system which includes a Unifi Security Gateway P3 Router, a Unifi POE 60W Switch, a Unifi AP AC Pro Wifi Access Point, and a Unifi Cloud Key
When I first plugged in my Gold Genesis, hardwired internet worked perfectly but the wifi wasn't giving me any internet. The wifi signal was good and strong but just no internet was coming through. My could Key was also not showing to be online and was not able to enter my Unifi system to look at my configurations. I held off on trying to figure it out for over a month and just placed the Genesis after my Router instead of in between the modem and router. This unfortunately gave it a Private Local IP so it was 99% harder for people to find if they were wanting to use the DPN and my connection.
I finally got fed up with my network topology and took another run at figuring this out. I feel kind of dumb as the solution was simple. After I put the Genesis back in between the Modem and Router, I waited for it to grab it's public IP and then tested wifi. Still no internet. Looked at my cloud key and still showed offline. So I went over my network closet and unplugged the Wireless AP and the cloud key from the POE switch, waited 30 seconds, then plugged them both back in. After a minute or so, wireless signal came back up and i had internet! I then checked my cloud key and it was online! I couldn't believe how simple it was to fix and how dumb I was to not have tried that before but I just didn't have the time to figure it out if it would've taken more than an hour.
This was my situation and I hope it helps you out.
