Message type: E = Error
Message class:  CNV_10520 - Conversion module of FI-CA FIKEY-logic 
Message number: 023
Message text: Field KONTL filled in the table DFKKSUM
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The SAP error message CNV_10520023, which indicates that the field KONTL is filled in the table DFKKSUM, typically arises during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. This error suggests that there is an issue with the data consistency or integrity in the financial documents being processed.
Cause: Data Inconsistency: The field KONTL (which usually represents a controlling area or a similar entity) is populated in the DFKKSUM table, but the system expects it to be empty or not filled for the specific operation being performed. Migration Issues: During the migration of financial data, if the source data does not align with the target structure or if there are missing mappings, this error can occur.
Configuration Issues: Incorrect configuration settings in the migration tool or in the SAP system can lead to this error.
Solution: Check Data Consistency: Review the data in the DFKKSUM table to ensure
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