Comcast/Xfinity VoIP says I need a new phone

[spooky3]

Can you offer any advice about this?

I have Xfinity VoIP, a one year old Motorola cable modem, and a Panasonic phone (2014) with several headsets. In the past week or so, two callers have told me they couldn't get through. Sure enough, after the first notice, I tried calling my home phone with my cell phone and it went to a recording that the phone was out of service. I unplugged the modem and re-plugged it in, and the service was restored. But late today, another caller said she got that recording so called me on my cell. I used my cell again to call my home phone, again got the recording, again disconnected the modem and reset it, and again service was restored.

Because I have no idea why this is happening, I spent a half hour with tech support at Xfinity and was told that he couldn't find any problem, but that my home phone was near its end of life so that was the problem. I told the agent that I didn't think so, because it didn't explain why I was able to restore service by resetting the modem. He said that resetting the modem resets the phone too.

Now, you may know that Comcast is notorious for blaming problems on everyone else. So I doubt that the phone is the problem - Amazon still sells lots of Panasonics that are only slightly newer than this model AND some that are older.

If you have had this experience, what do you think?