CANNOT Preview OR VIEW A ON-DEMAND MOVIE

After 20yrs w/DTV about ready to leave for other options - about 1 month ago began for 1st time in new place 18mos ago getting a pop-up error message "Not Connected to Internet" & for a month did all the things Support has you do - Unplug, Reset, Etc. without success. No option available to Preview an On Demand Movie & when select Watch Now get different messages including Error 303 but the movie never starts. All the time the Genie Box is Ethernet connected, my Router WiFi is connected with several devices all operating without issue.

So I call DTV Tech support spend over 1hr on phone doing all the same things I had done with the same result. They set up appointment for Tech to come - spend 4 hours - the tech leaves after changing out Genie (same 2019 mfg date) NO CHANGE Did NOT Fix. Then yesterday had to spend almost 2 hours w/ATT Billing to correct record error showing my old house which was torn down 2yrs ago as the Service Address to be the same as the Billing Address where we live now.

I reply to the DTV contractor Text about the result - I get no reply - I call the phone # just get recording.

VERY Disappointing & Frustrating!