Diagnosis
This error has 2 possible causes:
1.) The fields contract number, flow type and contract type are notindicated in FI as ready for input. The FI incoming payment documentcreated transfers an initial flow type to financial assets management.The same applies to the fields contract type and contract number.
2.) No IP flow types are maintained in TZB06 for the debit positionflow type.

Procedure
1.) Maintain the posting key table. You might also have to maintainT004F.