UPNP

I am running my own Wi-Fi and my Xfinity Gateway is just set to Bridge Mode. My Wi-Fi has UPNP enabled but the devices hardwired into the Xfinity Gateway (http://10.0.0.1)may not have that option active. The default username and password of admin and password do not work. How can I reset this so I can see my settings? I chatted and spoke with agents and no one can assist me. This was working fine less than 24 hours ago.