Message type: E = Error
Message class:  EDOCUMENT_IN_EINV - eDocument Inda eInvoice 
Message number: 065
Message text: User GSTIN should be seller GSTIN or e-Commerce GSTIN to create eInvoice
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The SAP error message EDOCUMENT_IN_EINV065 indicates that there is an issue with the GSTIN (Goods and Services Tax Identification Number) being used in the e-invoice creation process. Specifically, the error states that the user GSTIN must be either the seller's GSTIN or an e-commerce GSTIN.
Cause: Incorrect GSTIN: The GSTIN provided in the e-invoice does not match the seller's GSTIN or is not a valid e-commerce GSTIN.
Configuration Issues: There may be a misconfiguration in the SAP system regarding the GSTIN settings. User Role/Permissions: The user attempting to create the e-invoice may not have the appropriate permissions or roles assigned to use the specified GSTIN.
Solution: Verify GSTIN: Check the GSTIN being used in the e-invoice. Ensure that it matches the seller's GSTIN or is a valid e-commerce GSTIN. You can find the seller's GSTIN in the vendor master data or the relevant business partner information in SAP. Update GSTIN: If the GSTIN is incorrect, update it to
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