HBO Max can’t verify my subscription

When I go into the HBO Max app on my xfinity it tells me that it can’t verify my subscription and my xfinity subscription has expired. Thanks be talked to four customer service agents who passed it along to a tech who came out (which I knew was not going to fix anything because how could he) and he said I have to contact HBO. Why would I when it’s obvious that xfinity is not sending the right signal to the app. 
If anyone can help that would be fantastic since Comcast can not.