Xfinity stream app not working on Samsung tv

I am frustrated like every other customer that owns a Samsung tv.  I don't understand why the on demand content works on the Xfinity app on my Samsung tv, but none of the live streaming channels will work!  I have tried over 20 different live streaming channels and none of them work.  All of my other apps on the TV work fine as well.  I have completely removed the app and reset my Samsung tv, plus I reset the Xfinity TV box connected to my other tv.  I've tried everything and so I believe it is a Comcast Xfinity issue and not my TV!  Please Comcast can you look further into this issue and contact Samsung if you need to... Pleeeeaaaassse help me!!?