GR Posts to Wrong OBYC Transaction

Dear SAP Consultants,

When posting normal GR of Semi Finished (Valuation Class 7901) from PO (Mvt. Type 101), the system posts to GL account linked to GBB - VBR instead of BSX, the following error appears "Account requires assignment to CO object"

Here are the accounts maintained

Valuation Class BSX GL Describtion GBB - VBR GL Describtion ROH (3000) 1212100 Row Mat. Stock 3121210 Row Mat. Consumption Semi Finished (7901) 1212600 Semi Finished Stock 3121230 Semi Finished Consumption

When posting GR of Row materials it posts to BSX (1212100), Balance sheet account no CO object required and no errors.

When posting GR of Semi Finished it posts to GBB - VBR (3121230) not BSX !! How did this happen ?

Any advice ? How's the mapping done between MIGO and OBYC transactions ?

Thank you.

Regards,

Abdullah Galal