Try Again Error During Port Forwarding

We consistently get a "Try Again" error while trying to set up Port Forwarding on a PC in our home. We have restarted our gateway, but that has not helped. Looking for something specific that could be the problem. 

Did something change when we recently changed our package with Xfinity?

Previously, we were able to forward our ports locally on our gateway via 10.0.0.1. Now it says to do it through the Xfi web portal. When navigating to Port Forwarding in advanced settings only one port forward is visible, while there were multiple before. When trying to add a new port forward, we get the Try Again error every time.