Incoming calls going straight to Voice Mail

We have determined that incoming calls to our home phone are going straight to Xfinity Voice Mail.  We can make outgoing calls and our internet is fine. But phone calls are getting forwarded to voice mail without ringing even once at home.

We checked the call logs and see we have had many incoming calls, yet while a call shows up on the TV via X1, the phone does not ring. When we tried calling the home phone ourselves using our cell phones, we found it goes directly to voice mail.

Chatting with an Xfinity agent and seeing some solutions online to people who had similar problems, it is suggested that you go to the Call Forwarding section in Voice settings. But when I do go there, it shows "Sorry! Unable to process your request. Please try again." So I cannot access that section.