"You home internet is offline" - Xfinity App (Internet IS online however)

I just upgraded my modem through an Xfinity store (nightmare story, post coming soon) and the internet is working fine (getting ~600 mbps although paying for 1200 :\) but the Xfinity app shows "Your home internet is offline".

I suspect it might have something to do with another modem being attached to the app (part of the nightmare story).  The store originally gave me the wrong modem for the 1200mbps plan I wanted (not to mention the wrong cable box, which I wound up returning and just canceling that service) so I had to go back, wait in line again, and be issued the correct modem for the plan.

I look forward to your swift reply, Xfinity Customer Support.

-JHW