TDS paid under old regime instead of new

The system has incorrectly mapped your TDS payment. To fix this, log into TRACES to file a Correction Statement to manually map the challan to the correct period. If the portal remains unresponsive or locked, contact the TRACES Helpdesk with your grievance ticket numbers, or visit your jurisdictional Assessing Officer with physical proof of payment to request a manual adjustment of the challan mapping in the system.

Thanks Ashok but the traces does not allow to select this year as its the old regime so goes to the old portal and there its restricted only to 2025-2026 financial year. I have written to helpdesk no feedback so far waiting else I would have to visit the AO in person.

Few things to unpack here because the fix depends on what type of TDS filing this is.

Scenario 1 ,  employer deducted TDS using old regime slabs:
If you did not submit a new-regime declaration to your employer, they default to old regime. For remaining months, submit the declaration form requesting your employer to recompute TDS under new regime going forward. For months already deducted at old-regime rates: file your ITR-2 or ITR-1 under the new regime ,  the excess TDS comes back as a refund. You override the employer regime choice at ITR filing stage.

Scenario 2 ,  TDS return (Form 24Q or 26Q) filed with wrong financial year:
Log into TRACES as deductor. Under Defaults, click Request for Correction. The correction statement lets you amend the FY, quarter, and deductee details. For a completely wrong-year filing, you may need to file a fresh corrected statement for the right period and let the incorrect one sit as cancelled after processing.

The system changing the date to the previous year is unusual ,  is this on the TRACES portal, the income tax e-filing portal, or a salary TDS challan screen? That detail helps narrow the exact corrective path. This TDS return correction guide (https://taxgarden.in/blog/tds-return-correction-revision-online-24q-26q-27q-traces-india-2026) covers both scenarios end to end.

Thanks again,

If it would have been only challan I would have let it be as it is but I already paid the challan and then realized after I got the demand. 

Have created ticket and grievamces will wait for the feedback else will go to the AO.

Its 26QB TDS by the way.