Credit memo accounting entry issue

We have configure credit memo in SD. Sales order type ZCMN with item category G2N

Create a pricing procedure ZCMNV with condition type ZCRP. This condition class selected  as "price"

Assigned Acckey As Z00.

Defined VKOA As "V KOFI RCOA FERT 01 04 Z00 682001".

Billing Document shows

Item         Description                            Billed Qty     SU       Net Value     Material

10           THAL - UREA-BAGGED(FG) 0.620           MT      0.78-           500000342

20           THAL - UREA-BAGGED(FG) 2                  MT      2.52-           500000342

30           THAL - UREA-BAGGED(FG) 3.420           MT     4.31-            500000342

Accounting Entry  generated as

Customer A/c           DR

Discount A/C            CR

which is Wrong.

It should be like

Customer A/c           CR

Discount A/C            DR

Kindly Suggest what is wrong in the config process.

Regards

Sanjay