SAP Message >2109 - Error in function module &2 for event &1

Diagnosis
The function module &V2& accessed to event &V1& is incorrect.
CASE &V3&
WHEN "1"
The clearing amount determined by the function module has to have thesame +/- sign as the payment amount determined by the payment program.This means that you cannot change the amount from outgoing to incomingpayment or vice versa.
WHEN "2"
The clearing amount determined by the function module must not belarger than the payment amount determined by the payment program.
WHEN "3"
The error described above (during posting of the clearing amount) hasoccurred. The line items specified for the clearing transaction weregenerated by the function module because the Internalclearing indicator was flagged.
WHEN '4'
With an item to be cleared (document number &V4&) our company canretain withholding tax. With such an item, the function module must notchange clearing amounts and discount amounts. It is thus not permitted,for example, to make partial payments for such items.
WHEN '5'
With an item to be cleared (document number &V4&) the customer canretain withholding tax. With such an item, the function module must notchange clearing amounts and discount amounts. It is thus not permittedto make partial payments for such items.
ENDCASE

System Response
Payment program termination.

Procedure
INCLUDE FICA_NA_OSS OBJECT DOKU ID TX