What does you current bill say about HBO/HBO MAX, if anything, in the TV
items specified in the "Regular Monthly Charges" section of the bill?
If it says you are supposed to be receiving HBO MAX, use the toilet, sit
down in a comfortable chair with a glass or mug of your favorite
beverage, and call Comcast's customer service number specified in the
"By Phone" listing in the "Contact" section of your bill to get
assistance (hopefully!).
We pay for HBO as a component of our Comcast TV services, not as a
stand-along subscription. For the better part of this past year, our
monthly bill showed that we were getting HBO MAX. However, when we
navigated to either the Apps or the Networks section of the On Demand
menu area and clicked on the HBO MAX icon, the screen would display
information that HBO MAX is coming soon to X1, but that for the present,
it could be watched on line or using iOS or Android apps. That was
accurate. About one week ago, we saw a notification in the settings
(gearwheel) area of our cable box menu that HBO MAX was now available on
X1. After that, when we navigated to the HBO MAX icon, the screen
refreshed to say that we were being connected to a third party
application, after which HBO MAX was displayed with no message that we
need to subscribe. Works for us now. Good luck!