Resolution of Potential Double Taxation on NSC Interest Due to AIS Mismatch in FY 2023-24

Background:
I had a National Savings Certificate (NSC) that I redeemed in the current financial year (FY 2025-26). The full maturity amount—including all accrued interest—was credited to my account this year, and I paid advance tax on the interest income in anticipation of including it in my ITR for this year.

Last Year’s Issue (FY 2023-24 / AY 2024-25):
The post office (Postmaster General, Chennai City Region) reported accrued interest from my NSC for FY 2023-24 in the AIS (Annual Information Statement). I was not aware of this when I filed last year’s ITR, so I did not report this interest income at that time.

AIS Feedback Process:
After receiving a notification from the Income Tax Department, I submitted feedback on the AIS, initially denying the reported income since I hadn’t recognized it. The post office rejected my feedback, confirming their information was correct. Realizing the interest was indeed from my NSC, I later updated my feedback to “Information is correct” in July 2025.

Revision Hurdle:
The deadline to file a revised or belated return for FY 2023-24 has passed (it was December 31, 2024). So, I cannot update last year’s ITR to include the NSC interest for that year.

Current Year (FY 2025-26 / AY 2026-27):
I plan to declare the full interest income and claim the advance tax I paid when filing my ITR this year.

Key Concern:
Since I didn’t declare the NSC interest in last year’s ITR (now accepted as “correct” in AIS), I might receive a notice or demand from the IT Department for FY 2023-24.
If that happens, it appears I’ll have to pay tax on the same NSC interest for the previous year—even though I am already paying on the entire amount in this year’s return. I only want to pay tax on this interest once, not twice.

What I Need Clarification On:1. How can i settle the previous AIS issue (i want to pay the tax but dont know how to)?2. Do i have to wait for another notice to pay for it?
3. Even though i want to pay in the current financial year (but some people are suggesting to not mix it up with the last year), so what to do?