Cisco DPC3939 not supported?

When I click "add or manage devices", the message apears "It looks like you'll need some help managing your equipment. Please contact us..." but the automatic responses don't seem to have anything to do with this particular model. When I click "return a device", to see if I can switch to the newer xFi gateway, it displays my Cisco DPC3939 but does not allow me to select it. 

The problem is my account shows that I have a WiFi network but even after managing the name, password, "broadcast WiFi name", etc. it is not visible to connect to. Is there something preventing my device (Cisco DPC3939) from functioning with WiFi? Or, if I need to upgrade to the newer xFi gateway, how can I do so, since I get error messages whenever I click "add or manage devices" or "return a device"?