prime video won't launch

Amazon prime no longer launches.  After using this app successfully for about 15 years, with xfinity, now I no longer have access to Amazon Prime through xfinity.  Looking for information about how to fix this is nearly impossible on this garbled website with limited (no) user support.  And I see this kind of problem dates back about five years or so.  No help.  No information.  No human to contact (though I saw one can make "direct contact" by following six or so "simple" steps).  

Yes, this is very frustrating.  The app launches on my home laptop/desktop and runs prime just fine.  My internet speed is through the roof and running like a top.  My router has been rebooted.  My LG TV updated with all apps and rebooted.  But . . . Amazon Prime still does not load.  

Oh yeah, BTW, the topics and tags etc are reallly uninformed for this sort of problem.

Anyone out there?