As I remarked in an earlier post of this thread, I have a series with several episodes. I'm not seeing what you described. That's why I suggested you eliminate any errors first. If the problem persists even though you've eliminated errors, you can then contact Roku Partner Success and explain to them what you're seeing. They are your last resource for resolving your issue.
FREE Windows desktop software for converting Direct Publisher channels to SceneGraph (SDK), for creating
BIF (Trick Play) files,
Roku (MRSS, JSON) feed files, and
FireTV feed files @
GitHub/rrirower.