Storyline won't complete in Sum Total

I have a Storyline 360 course with various knowledge checks and an acknowledgement at the end.  If the user clicks yes on the acknowledgment, the course should complete in Sum Total. What we are seeing is that if the user does not get most of the KC right, they get an incomplete.  Even if they click Yes on the acknowledgement.  It will complete if most of the KC are correct and the user clicks Yes.  I am told this is not a Sum Total issue.  Can you please advise?  I have used this course for a few years now and it always worked fine.  Thanks!