Message type: E = Error
Message class:  FKK_ID_AR - ARGENTINA: Legal report message class 
Message number: 056
Message text: External document data is missing in internal table EXTDOC
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The SAP error message FKK_ID_AR056 indicates that there is missing external document data in the internal table EXTDOC. This error typically occurs in the context of contract accounts receivable and payable (FI-CA) when the system expects certain external document information to be present but cannot find it.
Cause: Missing Data: The external document data that the system is trying to access is not available in the internal table. This could be due to: Data not being populated correctly during document creation or posting. Issues with the integration between different modules or systems (e.g., missing data from an external system). Incorrect configuration or settings in the FI-CA module. Inconsistent Data: There may be inconsistencies in the data that prevent the system from retrieving the necessary external document information. Custom Development: If there are custom developments or enhancements in the system, they might not be handling the external document data correctly.
Solution: Check Data Entry: Ensure that all required fields for
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