Wrong tax type for the supply

You split tax into CGST and SGST on a supply the portal considers inter-state — or the reverse.

What it means

The portal derives whether a supply is inter-state or intra-state by comparing your state code against the place of supply, then checks that the tax heads match. Same state means CGST + SGST; different states mean IGST. There is no valid invoice that carries all three. The total tax is often identical either way, which is exactly why this survives a manual review and fails an automated one.

Common causes

• Place of supply was set to the buyer’s billing state while the goods were delivered elsewhere, or vice versa.
• A bill-to / ship-to transaction was treated by delivery address instead of the bill-to party’s principal place of business.
• Accounting software defaulted the tax type from the customer master rather than from the place of supply on the invoice.
• A service was invoiced under the default recipient-location rule when a Section 12 exception applied.

How to fix it

1. For each flagged invoice, compare the first two digits of your GSTIN with the place-of-supply code.
2. Same code: the invoice must carry CGST + SGST and no IGST. Different codes: IGST only.
3. Correct the tax heads at source in your accounting system, not just in the JSON — otherwise it recurs next month.
4. Regenerate the JSON and re-upload.
5. If the original invoice already reached the customer, issue a credit note and a corrected invoice rather than silently reusing the number.