HST Tax Detail Report Doesn't Match Balance Sheet

On my tax detail report, the total of taxes paid/charged figure correctly matches the figure on my balance sheet, and the total taxes charged matches the figure on my balance sheet.  However the figure at the bottom of the Tax Detail report Net refundable ST collected from sales less paid on purchases" figure is way off of what we owe to CRA.  How is this possible and how do I get it to match the correct figure?