Message type: E = Error
Message class:  EDOCUMENT_IN_EINV - eDocument Inda eInvoice 
Message number: 012
Message text: Field 'Gstin'(Business Place) is not filled under node 'SellerDtls'
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The SAP error message EDOCUMENT_IN_EINV012 indicates that the field 'Gstin' (Goods and Services Tax Identification Number) under the node 'SellerDtls' is not filled. This error typically occurs in the context of electronic invoicing (e-invoicing) in India, where GST compliance is mandatory.
Cause: Missing GSTIN: The most common cause of this error is that the GSTIN for the seller (business place) has not been entered in the relevant configuration or master data. Incorrect Configuration: The configuration settings for the business place or the seller details may not be set up correctly. Data Entry Error: There may be a data entry error where the GSTIN is not populated in the invoice or document being processed.
Solution: Check Master Data: Ensure that the GSTIN is correctly maintained in the master data for the business place. You can do this by navigating to the relevant business partner or vendor master record in SAP and verifying the GSTIN field. Update Configuration: If the GSTIN
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