HBO Max

When setting up the app do I have to use my xfinity email or can I use a different email?  I have been trying to set it up using an alternate email but nothing seems to happen.  Actually I go around in circles.  I have put a code in several times and never get to an actual sign in page.  Also, could it be my dvr box?  I was able to see Pace  on one of the stickers on the bottom but didn't see anything like XG1v1, which I read is not a compatable box.  And yes I currently have HBO.