You may have done a day-end on the wrong date. This sometimes happens when you are not open on Sundays & on the Monday had run the dayend without changing the date to the Monday.
So, to correct this, go into the 4POSOffice program - Dayend - Dayend Reports.
Click once on the date that is incorrect, press d (Lower case) for date on the keyboard & type in the date that you wish that dayend to be for.