Complete course restarting in the middle

Hello, everyone!

if this is someone else already ask or resolve, i'm sorry you can redirect me if that's the case.

I have a scorm that mark complete by view numer of slides and everything goes smoothly.

But when, you come back AFTER finished course and its marked complete, the course restarts between 8 to 7 slides BEFORE last slide (not always the same slide but never the very last slide). Even when you have "complete" mark in the platform. Is this common? Do I have to change something? My course have 34 slides.