Message type: E = Error
Message class:  SLS_TEMPLATE - Messages for sales template 
Message number: 015
Message text: Item &1: EAN/UPC &2 is not defined
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The SAP error message SLS_TEMPLATE015 indicates that there is an issue with the EAN (European Article Number) or UPC (Universal Product Code) for a specific item in the system. This error typically arises when the system cannot find a valid EAN/UPC code for the item specified in the error message.
Cause: Missing EAN/UPC Definition: The item (identified by &1) does not have an associated EAN/UPC code defined in the system. Incorrect Item Master Data: The item master data may not be properly maintained, leading to the absence of the EAN/UPC. Data Migration Issues: If data was migrated from another system, the EAN/UPC codes may not have been transferred correctly.
Configuration Issues: There may be configuration settings in the SAP system that are not set up to handle EAN/UPC codes properly.
Solution: Check Item Master Data: Go to the material master record for the item in question (transaction code MM03). Verify that the EAN/UPC field is populated correctly. If it
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