why same value repeated in credit side and found in database

ahmedba

Balance credit debit price quantity description type document no ship date

-15000 15000 order 008 13/09/2012

0 15000 500 30 38mpa earth 06/09/2012

-25000 25000 order 009 13/09/2012

0 25000 500 50 38mpa earth 06/09/2012



Before two days I face this problem when I make sales order then I press post then invoice after this when I make customer statement report it show above data.as notice when I ship quantity 30 with price 500 it must show 15000 in debit side only. Why it show also 15000 in credit side what this problem and how I solve.

I open detailed cust .ledg entry table I found this data as above already exist in this table meaning the report not have any problem.