Missing navigation controls for an imported slide

Help! I imported a slide I previously created into a new storyline course I created. The problem is in preview and publish modes, there are no previous and next navigation controls for this slide. I messed around with the Slide Properties and the Player controls and cannot get the navigation controls to work. When I click on the next arrow, it will not advance and stays on the same slide. I had to add my own next button to the slide to enable viewers to get to the next slide. In story view, the slide (2.1) shows an arrow to 2.2 which seems to indicate that there is navigation and in Preview mode the navigation arrows are there, but they do not work.