Can't watch DirecTV on macbook air

I successfully signed into Directv and tried to watch a program from the guide. At first I had to download some stuff but then it appeared it would work. When I open a program it opens a viewing window and says "loading" and then "authorizing" but no image appears and the window controls don't work. I'm using Chrome but got the same response on Safari. I'm still running Mojave OS as I donlt dare to upgrade to Catalina yet.