Message type: E = Error
Message class:  FKK_SEPA - FI-CA: SEPA Mandate Management 
Message number: 001
Message text: Specify contract as reference as well as subapplication
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The SAP error message FKK_SEPA001 typically occurs in the context of the SAP Convergent Charging or SAP Contract Accounts Receivable and Payable (FI-CA) modules. This error indicates that a contract must be specified as a reference along with the sub-application when processing a SEPA (Single Euro Payments Area) transaction.
Cause: The error arises when the system requires a contract reference for a SEPA payment processing operation, but this reference is either missing or not properly defined. This can happen due to: Missing Contract Reference: The transaction does not have an associated contract that is required for the payment processing. Incorrect Configuration: The configuration settings for SEPA payments may not be set up correctly, leading to the system not recognizing the necessary contract. Sub-application Not Specified: The sub-application (like a specific payment type or method) is not defined in the transaction.
Solution: To resolve the FKK_SEPA001 error, you can take the following steps: Check Contract Reference: Ensure that the transaction
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