Message type: E = Error
Message class:  CNV_21523 - Personnel Subarea Rename 
Message number: 012
Message text: Multiple lines with personnel area &1 and old personnel subarea &2
Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.
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The SAP error message CNV_21523012 typically occurs during data migration or data transfer processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. This error indicates that there are multiple entries in the source data that have the same personnel area and old personnel subarea combination, which is not allowed in the target system.
Cause: The error is caused by the presence of duplicate records in the source data that share the same personnel area and old personnel subarea. This can happen due to: Data Duplication: The source data may have been incorrectly populated, leading to multiple records for the same personnel area and subarea. Data Migration Issues: During the data extraction or transformation process, records may not have been filtered or aggregated correctly. Inconsistent Data: The source system may have inconsistencies or errors in how personnel areas and subareas are defined.
Solution: To resolve this error, you can take the following steps: Identify Duplicates: Review
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