Error Airplay iPad to AppleTV3

When I AirPlay HBOMax Contents from my iPad to my AppleTV3, the AppleTV3 shows error message “An error occurred loading this content. Try again later”. Both iPad and AppleTV are in the same room, on the same Network, have been updated, restarted & reset, all to no avail. I am successfully Airplaying YouTube Contents from my iPad to the AppleTV. Thank you for taking my question.