Netgear Nighthawk and Netgear Nighthawk extender WiFi signal issues with Xfinity router

I'm trying to boost the Wi-Fi coverage in my house. I currently have service through Xfinity.

I'm using a Netgear Nighthawk extender to test the signal.

The weird thing is, when I try to manually select a network, I can see all my neighbors' signals, but mine isn't showing up at all. Any idea what might be causing this?

..it’s possible you've got the setting turned on in your router's WiFi menu to hide the SSID.

That’s an interesting idea, but I don't see that option anywhere