Hi, Bhagat
As the discussion on account assignment
u have to maintain the account assignment as to maintain in the following way
V KOFI CAHU 0001 02 A4 ERL 93110
V KOFK CAHU 0001 02 A4 ERU 93111
make sure that A/C group for Customer and A/C group for material has to assign for the customer ur creating sales order and the material which u enter in the sales order
try this , again if u get error, please paste the screen shot of A/C assignment analysis of VFO2
Regards
Yuvaraj.