Smartlist Totals do not match

Hi,

I ran a Smartlist Report from 'Customer' to get my totals, this was just prior to the monthend close. All batches in SOP and Rec were posted. I ran a detail TB before I did the Aging, when I checked the totals, the TB and the Smartlist the aging bucket 181 and over did not match.

I normally run this report and the  totals would match that of the TB.

The difference has been identified but not sure where to look or how to start to find the documents which make up this value.