Cannot connect to Nighthawk EX7000 after setup [REPOST]

[Aquanex2]

This is a repost. I posted my initial problem in the wrong section of the forum...

I was having issues with my Nighthawk, so I reset it and attempted to reconfigure it. Everything seemed fine. I was able to connect it to my Xfinity modem and I could see the SSID I set it to in my list of Wi-fi networks. Though when I try to connect to it, I get a "failed to connect" message every time. I don't know what to do and I really don't want to get a new one as this one is only about a year old. It is also worth noting that I have already looked up documentation and followed the steps for both WPS and web configuration methods. Both leading to the same result.

Any help is greatly appreciated.

[plemans]

what firmware version is on it? 

What router are you connect it to? 

If you hardwire into the ex7000, are you able to log into it and view its status page once you have it setup? And does it work wired? 

[Aquanex2]

Firmware V1.0.1.90_1.0.156
Xfinity cable modem
I can plug in directly to the Nighthawk and get internet, but I cannot connect over Wifi. I can see it in my list of Wifi connections as I named it. I turned off the single naming convention and named each 2GHz and 5GHz SSID myself. Both give me "Failed to connect" errors.

[plemans]

All wireless devices fail to connect?

Try changing the wireless ssdi name and password. Make sure to avoid special characters/spaces in the ssid/password

[Aquanex2]

I've tried it on my laptop and multiple phones but it's the same. Laptop says "Can't connect to this network". I've changed the name slightly, there was an underscore but I removed it. Password has no special characters.

[plemans]

tried downgrading the firmware a version? 

[Aquanex2]

I haven't even upated firmware so why would I need to downgrade? Which firmware would I even downgrade to and how?