SAP Message >3748 - Error in interface for function module &1

Diagnosis
Function module FKK_WRITEOFF_WITHOUT_COMMIT can be used as anactivity in a mass run and to write off a document number. If thismodule is used as an activity, the open items to be written off in tableT_FKKCL must be transferred to the interface.
The call of function module &1 is not correct. The parameters in theinterface are not consistent.

System Response
Check the call of the function module.

Procedure
If the importing parameter I_USED_AS_ACTIVITY is set, no documentnumber (I_OPBEL) must be entered for selection in the interfaceto the function module. At the same time, the internal table T_FKKCL
must be filled and the currency (I_WAERS) predefined in whichit is to be written off.
If the importing parameter I_USED_AS_ACTIVITY is not set, adocument number (I_OPBEL) must be entered for selection of theopen items in the interface to the function module. At the same time theinternal table T_FKKCL must not be filled.