No reply yet so I'll jump in. IMHO there are too many section properties involved to know exactly why this is without guessing and they often have to work in harmony. Did you examine such things as "keep with next", "group together on one page" (or not), etc.? You turn on Sorting and Grouping by right clicking on report and choosing it from the menu. You may have to upload a zipped copy of your db at some point if you don't find or receive an answer to what you need. You can always mask sensitive data.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.