Posting key determination in MRKO

Hi Experts,

I would like to understand how the posting key is determined for consignment settlement in MRKO.

When we are trying to settle the consignment using MRKO for 262/k movement type, it is looking for posting key '21' since last week, but before that it was checking for posting key '31' when creating the FI document for the same 262/K.

So, I am curios to know what setting in SAP will determine the posting key for movement type 262/K for creating FI document in MRKO.

Your help will be highly appreciated.

Thanks in advance

Regards

VJ