Message type: E = Error
Message class:  FKKPARTSET - Partner Settlement 
Message number: 205
Message text: Source transaction &1 &2 for partner &3 was released for billing
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The SAP error message FKKPARTSET205 indicates that a source transaction (like an invoice or billing document) has already been released for billing for a specific partner. This typically occurs in the context of contract accounts receivable and payable (FI-CA) when trying to process a transaction that has already been finalized for billing.
Cause: The error is triggered when: You attempt to release a transaction that has already been processed for billing. The transaction is in a status that does not allow further modifications or releases. There may be an attempt to duplicate a billing process for the same partner and transaction.
Solution: To resolve this error, consider the following steps: Check Transaction Status: Verify the status of the source transaction (e.g., invoice, billing document) in the system. Ensure that it has not already been released for billing. Review Billing Documents: Look for any existing billing documents related to the partner and transaction. If a billing document already exists, you
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