Flex Technicolor TX061AEI Paramount Plus app not loading programming

I have the xfinity Flex Technicolor TX061AEI streaming box connected through HDMI to my TV. For a month everything worked fine but for the last week the paramount+ app will not play programs. All other Flex apps, ie, Netflix, Hulu, etc. work just fine. The Paramount+ app lets me navigate and perform all other functions but will not play programs. In fact, I can stream live TV, play trailers, and play extras but when I try to play an actual program or movie I simply get a spinning loading wheel. Eventually the function times out and I get the error message, "Something went wrong. Please try again". I've reset the Flex streaming device and my modem several times. All other Flex apps work fine. There is also no problem streaming on my iPhone with the Paramount+ app. I'm experiencing this problem ONLY on the Flex Paramount+ app. I've been in contact with Comcast and Paramount customer service several times and have been told they are elevating my case. I haven't heard squat. Please advise.