Message type: E = Error
Message class:  CNV_21536 - Action Rename 
Message number: 012
Message text: Multiple lines with old personnel action &1
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The SAP error message CNV_21536012, which indicates "Multiple lines with old personnel action &1," 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 are multiple entries in the source data that correspond to the same personnel action, which can lead to inconsistencies or conflicts during the migration process.
Cause: Duplicate Entries: The primary cause of this error is the presence of duplicate records in the source data for the same personnel action. This can happen if the data extraction process did not filter out duplicates or if the source system has redundant entries. Data Integrity Issues: There may be issues with data integrity in the source system, where multiple records exist for the same personnel action due to incorrect data entry or system errors. Incorrect Mapping: The mapping of fields during the migration process may not be set up
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