Getting error message when billing document release to accounting in vf02 tcode

Hi all,

In vf02 tcode i am trying to post/change the billing document but getting an error message. first i entered the billing document and i clicked the flag release to accounting it is showing an error messsage "field partner pc is a required field for g/l account 5008 45100000". Message no. F5808

i have debugged the vf02 tocde and i found that the net value if it is '0' it is showing the error but when i entered any amount for the field netwr i mean if it is not equal to zero then the billing document is posting correctly. i don't know wheather it is a standard issue or not ?

Also i found that for the failure senario the vbrk-rfbsk value is not equal to 'C' and for the success senario i checked the status value is equal to "C'.

i also checked the tcode 'vf05n' it is showing the billing documents which are not posted to accounting..

can any one please explain me why the error message is comming, please provide me if any solutions are there.

thanks in advance,

koushik.