Gateway not showing up on app/no access to wifi settings via app

To whom it may concern,

My WiFi works and I have access to the internet through it, but the xfinity app does now show my gateway device. I do not think that my gateway device is linked to my account properly. I believe this is also inhibiting my ability to edit my wifi details via the app and also is inhibiting my ability to port forward as I want. 

I've tried reinstalling the app many times

and I've restarted my gateway a handful of times to no avail.

I'm under the impression that all of these issues are caused by my gateway not being properly linked to my account. I am prompted to buy/rent a gateway on the app and on the website when I'm logged in despite the fact that I already have one from xfinity. 

What should I do to fix this?

Thanks.