Can't see my info in GANTT chart

I'm stuck on an issue with an Excel GANTT chart and hoping someone can help. I have entered 36 rows of data in the Project Tracker sheet, but only lines 1-6 are appearing as a chart that I can see. I can't see any formulas attached to the lines that are hidden but was wondering if "Scrolling increment' on the GANTT chart sheet might be significant - I have no idea what it means. Thanks!