Message type: E = Error
Message class:  CNV - Conversion: Messages for Conversion Services (CNCC) 
Message number: 764
Message text: Data had been saved already
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The SAP error message CNV764 ("Data had been saved already") typically occurs during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or other data migration tools. This error indicates that the system has detected that the data you are trying to save or process has already been saved in the database, which can lead to duplication or inconsistencies.
Causes:
Duplicate Data: The most common cause is that the data you are trying to import or process already exists in the target system.
Incorrect Mapping: There may be issues with the mapping of fields or records, leading to attempts to save the same data multiple times.
Process Re-execution: If a migration process is re-executed without proper cleanup or rollback, it may attempt to save data that was already processed.
Transaction Management: Issues with transaction handling, where the system believes the data is still in a pending state.
Solutions:
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