Can not log into Directv app!! - DirecTV

I just got Directv and AT&T unlimited data plan on all my phones and my tablet, but i can not log into the Directv app keeps giving me external System failure on my tablet and on my phones it acts like it is going to let me log in but they says something went wrong to try back later or uninstall the app. I have done everything i can think of, but still can't log in... Any help would be greatly appreciated.

This question, "Can not log into Directv app!!," is about DirecTV channels, programming, equipment, and sports.