How To Fix CNV_NCE_BAS109 - 1:1 mapping values for &1 and &2 result in duplicates

CNV_NCE_BAS109 - Overview

• Message type: E = Error

• Message class: CNV_NCE_BAS - Number conversion engine: messages

• Message number: 109

• Message text: 1:1 mapping values for &1 and &2 result in duplicates

Self-Explanatory Message

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CNV_NCE_BAS109 - Details

• The SAP error message CNV_NCE_BAS109 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 there are duplicate values in the mapping of source and target fields, which violates the requirement for unique mappings.
  
  Cause:
  The error message "1:1 mapping values for &1 and &2 result in duplicates" suggests that the system has detected that the values being mapped from the source to the target are not unique. This can happen due to several reasons:
  
  Duplicate Source Values: The source data contains duplicate entries for the field being mapped, which leads to multiple records trying to map to the same target value.
  Incorrect Mapping Configuration: The mapping configuration may not be set up correctly, leading to unintended duplicates.
  Data Quality Issues: The source data may have quality issues, such as missing or incorrect identifiers, causing multiple records to be treated