Message type: E = Error
Message class:  IT_CUP_CIG - CUP/CIG Number Capture at Vendor Invoice for Italy 
Message number: 055
Message text: Vendor &1 data already migrated
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The SAP error message IT_CUP_CIG055, which states "Vendor &1 data already migrated," typically occurs during the migration process of vendor data in SAP systems, particularly when using the Central Finance (CFIN) or Central Procurement (CUP) functionalities. This error indicates that the vendor data you are trying to migrate has already been processed or exists in the target system.
Cause: Duplicate Migration Attempt: The vendor data you are trying to migrate has already been migrated in a previous run, leading to a conflict. Data Consistency Issues: There may be inconsistencies in the data that prevent the migration process from recognizing the vendor as a new entry. Incorrect Migration Logic: The migration logic may not be correctly identifying new versus existing vendors.
Solution: Check Existing Data: Verify if the vendor data already exists in the target system. You can do this by querying the vendor master data in the relevant tables (e.g., LFA1 for vendor master). Review Migration Logs:
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