Message type: E = Error
Message class:  FKK_ID_PT_SIGN - Digital Signature Portugal FI-CA/IS 
Message number: 306
Message text: Prerequisite Document data is not available
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The SAP error message FKK_ID_PT_SIGN306 indicates that the prerequisite document data is not available for a specific operation in the SAP system, particularly in the context of contract accounts receivable and payable (FI-CA) or related modules. This error typically arises when the system is trying to process a transaction that requires certain prerequisite data that is missing or not properly configured. Causes: Missing Prerequisite Document: The document that is required for the transaction (like an invoice, contract, or payment) does not exist or has not been created. Incorrect Document Status: The prerequisite document may exist but is in a status that does not allow it to be referenced (e.g., it might be blocked or not yet posted).
Configuration Issues: There may be configuration settings in the SAP system that are not set up correctly, leading to the inability to access the required document data. Data Inconsistencies: There could be inconsistencies in the database or issues
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