Unable to process to PO because of Account assignment and G/L

Hi All,

I am practising on the process of creating the PO in SAP. While Creating PO, I am unable to process the PO to completion because of Account assignment and G/L category. I am not understanding the mapping between those two fields.

Please help me to understand against what account assignment, which G/L has to be picked. I see there are lot of G/L on the picker.

Thanks,

Anil