how to make condition value inactive

Hi Gurus,

I have scenario like this,

If condition value (KWERT) is equal or less than '0', then sy-subrc is set to '4' in order to make the condition type inactive during sales order creation or change.

For this I have written logic like this,

loop at XKOMV .
IF KOMK-VKORG = 'UK20' AND XKOMV-KWERT LE 0. "for sale org 'Uk20'
XKOMV-KINAK = 'X'.
SY-SUBRC = 4.
MODIFY XKOMV .
ENDIF.
ENDLOOP .

but it is not going to be inactive during sales order creating or change.

Can anybody help me in this regards,

Thanks,

Syed