Thanks for the posts.
If you're only experiencing the issue on HBO Max while other channels play fine, contact the channel provider's customer support team to report the issue and get help. Channels on Roku are maintained by the channel developer themselves. In this case, there's likely an issue within that specific channel that needs to be addressed with an update from the channel developer.
You can contact HBO Max Support here: https://help.hbomax.com/
Thank you for your understanding.
All the best,
Roku Forum Moderator