Message type: E = Error
Message class:  CNV_20340_CHECK - Message Class for 20340 Checks 
Message number: 012
Message text: Source value op. concern &1 cycle &2 assigned to multiple target values
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The SAP error message CNV_20340_CHECK012 indicates that there is a data inconsistency in the conversion process, specifically related to the assignment of source values to multiple target values. This error typically arises during data migration or conversion processes, particularly when using SAP's Conversion Tools (like the SAP S/4HANA Migration Cockpit or other data migration tools).
Cause: The error message suggests that a source value (in this case, an operational concern identified by &1) for a specific cycle (&2) is assigned to multiple target values. This can happen due to: Data Duplication: The source data may have duplicate entries that map to different target values. Incorrect Mapping: The mapping configuration between source and target values may not be set up correctly, leading to multiple target assignments for a single source value. Business Logic Issues: The business rules defined for the conversion may not be correctly implemented, causing conflicts in how values are assigned.
Solution: To resolve this error,
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