If you have entered the HSN code instead of the SAC code for a service item in the invoice creation page, you will encounter this error message. To verify the item type associated with the invoice:
The item type will be displayed below the line item in the table.
Pro tip: Go to the e-invoicing portal to check the HSN/SAC code of your item.
After saving the changes, you will not encounter the error message when you push your invoice to IRP.
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