In Multi-Panel Page of Across Report columns overflow into space between panels after 2nd panel on t

 I have a group-across report that uses 6 horizontal landscape-sized (8.0 inch x 10.5 inch) panels.  The report skips over the vertical seam between panals on the first two panels, then the printing spans across the third vertical seam, printing part of the column on the third panel and the rest on the fourth panel, with the margin space between.  I have been unable to correct this using page protection.  The only thing that has made any difference is adjusting the size of the physical page used as the panel size in constructing the logical page. 
How do I prevent the division of a column across the gap between physical panels of a multi-panel logical page?