Message type: E = Error
Message class:  CNV20305 - Messages for conversion packages in CO 
Message number: 706
Message text: Entry for field &1-&2 already exists in CNVFIELDS
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The SAP error message CNV20305706 indicates that there is a duplicate entry for a specific field in the CNVFIELDS table during a data migration or conversion process. This error typically arises in the context of SAP's data migration tools, such as the SAP S/4HANA Migration Cockpit or other data conversion scenarios.
Cause: The error occurs when the system detects that an entry for the specified field (indicated by &1 and &2 in the error message) already exists in the CNVFIELDS table. This can happen due to: Duplicate entries being created during the data migration process. Incorrect configuration or mapping of fields in the migration project. Manual entries or modifications that lead to conflicts.
Solution: To resolve this error, you can follow these steps: Check for Duplicates: Access the CNVFIELDS table in the SAP system and search for the entries corresponding to the field names indicated in the error message. Identify any duplicate entries that may exist. Remove or Modify Duplicates: If duplicates
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