Quiz slides sometime shows Prev/Next and not Submit

I do LMS support at my company, and I had a Storyline user with this same issue.  I took his Storyline file and found that on the Results page of his quiz, when I edited that page, he had a timer turned on that was set to start on the first slide.  The timer was set to 120 minutes and the quiz would then turn off.  I'm not sure about the logic of that setting or why anyone would want to cause their course to self destruct after 2 hours, but turning that off fixed the problem.  When we tested, we could start his course and jump in the menu to the quiz and it would work. But, if we went through the course slide by slide,  when we got the quiz, there was no Submit button. Turning off this quiz timer setting seems to fix the problem.