Airplay from my iPad to my Roku sound bar isn’t showing video, only audio.

I’ve done everything to get HBOMAX to stream from my iPad, everything is up to date, and I can see the menu to pick videos, but when I try to play a video, I get no picture only sound. Screen mirroring does the same! I see everything from my iPad but when I try to play the video, no picture. I’ve been chatting with support and they haven’t figured out what the problem is. HALP!