Message type: E = Error
Message class:  NAA - Subsequent settlement (Purchasing) 
Message number: 475
Message text: A dataset with this key combination already exists
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The SAP error message NAA475, which states "A dataset with this key combination already exists," typically occurs in the context of data management within SAP applications, particularly when dealing with datasets or master data records. This error indicates that the system has detected an attempt to create or modify a dataset that already exists with the same key combination.
Cause: Duplicate Entry: The most common cause of this error is that the dataset you are trying to create or modify already exists in the system with the same key fields. This could be due to a previous entry that was not deleted or an attempt to create a new entry with identical key values. Data Migration Issues: If you are migrating data from another system or performing bulk uploads, there may be duplicates in the data being imported. Incorrect Key Fields: The key fields used to identify the dataset may not be correctly defined,
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