HBO Go help please!!!!

I am trying to sign in with HBO Go on a new Roku I just got but I keep getting a message saying "this is a sub account, please register your primary account first." But it doesn't give me an option anywhere to register any primary account. It asks for my provider and when I select AT&T Uverse it automatically tries to log me in without giving me any options to change anything. It's doing the same thing on the HBO Go website where I have never had that issue before. I've seen a couple other people ask a similar question on this forum but no answeres matched my situation. Please help!!!!