Multiple channels not accessible

SeeFor the past 3 months multiple fire sticks and multiple TVS have not been able to get a number of very useful Xfinity stream channels. I have Uninstalled and Uninstalled and reinstalled the app cleared the cache and data Signed out and signed in Unplug the television and router and modem for over a minute eachreinstalled. Nothing has helped. Reading the answers given in the forum has not been of any benefit to me. above.  Answers on forum have not helped.