How can I solve a PA transfer structure problem?

When I try to run the atranscation co88 “Actual Settlement Production/Process Orders” SAP CO, comes out the following error:

Diagnosis

• There is no value field assignment for cost element 7771005 / variance category SCRP in PA transfer structure Z6, or

• PA transfer structure Z6 has no assignments, or

• No "Origin" is maintained for the assignments in PA transfer structure Z6 (cost element group and, if applicable, variance category)

Procedure

Action by system manager:

Complete the PA transfer structure or assign another PA transfer structure to the sender.

The system takes the default PA transfer structure from the settlement profile when you maintain the settlement rule for the sender. Maintain the settlement profile as necessary.

Proceed

I think that to fix it must go fix it I must go to customizing…but don’t now where and how..!!

Could anyone please help me to solve it?

Thanks in advance,

Angelo