I looked at this form after I couldn't Activate HBO on my Amazon Fire TV 4K. I was able to figure out what was going on and hope this helps others. There's two Apps. HBO GO and HBO Now. You need HBO GO and NOT HBO Now if you are a comcast XFinity customer. It was a bit confusing but just download HBO Go and then sign in with your Comcast account and use the code you get. The code from HBONOW will not activate on hbogo.com/activate.
... View more