TaxTMI 
TaxTMI 
11 Sep 2026 
When a buyer accidentally rejects a valid Credit Note (CN), the system automatically cancels your tax reduction and claws back the GST amount by adding it to your output tax liability.
To fix this and make your returns match, your action plan depends entirely on when the buyer rejected the document. Below are the two definitive workflows.
Workflow 1: Same-Month Rejection (Fixed via Form GSTR-1A)
Use this if: You issued the Credit Note this month, filed your GSTR-1, and the buyer rejected it before you filed your current month's GSTR-3B.
Step 1: Navigating the Portal
- Go to Services Returns Returns Dashboard.
- Select the current filing month and look for the tile labeled GSTR-1A (Amendment of outward supplies). Click Prepare Online.
Step 2: Table Selection & Column Mapping
Inside GSTR-1A, scroll down to the Amend Record Details section and select Table 9 - Amend Credit/Debit Note (Registered). Search using your original note number, click Amend Note, and copy the exact, unchanged details into the columns:
| Portal Column / Field Name | Value to Enter (Unchanged Data) |
| Revised Note Number | Re-type the identical original note number. |
| Revised Note Date | Keep the original date of issuance. |
| Original Invoice Number & Date | Enter the underlying B2B invoice number and date. |
| Note Type & Value | Select Credit Note and enter the total gross value (Taxable + GST). |
| Taxable Value Box (e.g., 18%) | Enter the exact same taxable amount as originally filed. |
Click Save, click Generate Summary, and file Form GSTR-1A.
The Result
Because this happens in the same month, the portal instantly recalculates your tax profile. It removes the forced tax clawback out of Table 3.1 of your current GSTR-3B. Your current GSTR-1 and GSTR-3B tally and match perfectly right now, and the document re-appears in the buyer's IMS for them to click "Accept".
Workflow 2: Later-Month Rejection (Fixed via GSTR-1 Table 9C)
Use this if: You issued the Credit Note in a previous month (e.g., May), but the buyer rejected it in a later month's return cycle (e.g., July), and that previous window is now completely frozen.
Step 1: Navigating the Portal
- Open your current open, un-filed standard GSTR-1
- Scroll down and click directly on Table 9C - Amended Credit/Debit Notes (Registered).
(Note: You cannot use Table 9B because the portal will block you with a "Duplicate Note Number" error).
Step 2: Table Selection & Column Mapping
Search for the old financial year and original note number, click Amend Note, and populate the amendment grid with the exact same historical records:
| Portal Column / Field Name | Value to Enter (Unchanged Data) |
| Revised Note Number | Keep this identical to the original note number. |
| Revised Note Date | Keep the original historical date; do not use today's date. |
| Original Invoice Number & Date | Re-map the exact underlying invoice details linked previously. |
| Note Type & Value | Select Credit Note and enter the full original gross value. |
| Taxable Value Grid | Enter the value under the applicable tax rate grid (e.g., 18%). |
Click Save and file your GSTR-1.
The Result (The Temporary Mismatch)
Because you entered identical values, Table 9C calculates a "Zero Delta" (Rs. 0 change) for this month, adding nothing to your current GSTR-1 summary. However, your current GSTR-3B is carrying a forced tax addition from the buyer's past rejection. Your GSTR-1 and GSTR-3B will not match immediately.
How to Clear the Table 9C Mismatch
Under the modern rules, the outward liability cells in GSTR-3B are hard-locked. You cannot manually type over the mismatch error. To clear it:
- File your GSTR-1 with Table 9C to push the document back into the active matching stream.
- Instruct your buyer to log into their Invoice Management System (IMS) dashboard, locate this fresh entry, and click "Accept".
- The moment the buyer accepts it, the portal's backend logs the data handshake, automatically drops the forced tax clawback from your GSTR-3B, and makes your returns match perfectly.
Comparison Checklist for Your Reference
| Feature / Step | Same-Month Rejection (Workflow 1) | Later-Month Rejection (Workflow 2) |
| Portal Form to Use | ||
| Specific Table Selected | Table 9 (Amend Note) | Table 9C (Amended Notes) |
| Bypasses "Duplicate Code" Error? | Yes | Yes |
| Do the returns tally right away? | Yes. GSTR-3B auto-corrects instantly. | No. Mismatch stays until the buyer clicks accept. |
| Required Buyer Action | Must log in and click Accept. | Must log in and click Accept. |
Thank You for Reading
Thank you for taking the time to read this article. I appreciate your attention and interest in the topic. I hope the insights shared here prove valuable in your professional endeavours. Your feedback or perspective is always welcome. please feel free to connect or continue the conversation.
Disclaimer
While every effort has been made to avoid errors or omissions in this document, the author makes no warranty, and expressly disclaims any obligation, that: (a) the information contained herein will be complete, accurate or up-to-date; (b) the results obtained from the use of such information will be accurate or reliable; or (c) the quality of such information will meet the user(s) expectations. The author is not responsible or liable for any loss, claim, delay, or damages, of any kind (including, without limitation, loss of profits or loss of savings) that may arise out of, or is connected with, any use of such information. The author expressly disclaims and will not be liable for any act or omission, or any consequence of any act or omission, by user(s) relying on the information in this document or any interpretation thereof. The user(s) should refer the original Government publications and/or notifications before any act or omission. Readers are encouraged to consult with qualified professionals to obtain advice tailored to their individual circumstances.