We recently added HBO Max to our AT&T TV(Now DirectTV Stream) package and we can't access it with the Roku on our Samsung TV. We can get it on our other TV with the At&T box. The Samsung/Roku TV has no apps to add it to-We are getting regular HBO, but not HBO Max. I did install it on Google Play. We asked AT&T for assistance, and it was determined the problem is with the Roku- not AT&T. I don't want to get HBO Max through the Roku channel- we had it before, and it kept displaying the message that the Roku was overheating when we watched HBO Max.
You should be able to add the DirecTV Stream app to your Roku, and watch it through that, since that how you subscribed. You won't be able to watch it on the standard HBO Max app, since you subscribed through DirecTV Stream. If you subscribed directly to HBO Max, you could watch it through the standard app.
DBDukes
Roku Community Streaming Expert
Note: I am not a Roku employee.
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