Able to activate Apple TV on only one of two tvs current running Xfinity. Both tvs are recent purchases and fully support streaming.

Extremely frustrating, why can’t I get Apple TV activated on both sets in my home?  Talked at length with xfinity customer service and they can’t fix the problem either; I was able to get Apple TV activated on the main box but not the other one.  From what I’ve read on this site, activation on the “main” box should automatically allow access on the other tv as well, but it doesn’t.

Xfinity reps are totally useless on this problem; anybody have any suggestions?