Can't play certain videos on Roku app

I use the Roku app on my TV almost exclusively for practice. Most of the videos work fine, but some do not. The most consistent problem I’ve had is trying to open Core Fusion Flow (Melissa) - whenever I try this, Guy’s Movement as Meditation opens instead. I have had a similar problem with another video, but unfortunately don’t recall which one. I don’t have this problem with the web site, so I can switch to using a laptop/tablet if this can’t be fixed.

Thanks in advance for any help you can provide.

Nathan