Resignation Confusion: Can My Employer Change My End Date After Signing?

I have the below issue.

I resigned on the 25th of January, and given my notice period is 3 months, I have requested for that to be shortened, requesting the 21st of March as the end date.

My manager is misled because the HR system shows a 4-week notice and accepts the 21.03 as the end date. I also received a termination letter stating my end date is the 21.03.

However, my manager realizes that the 4-week notice information was incorrect and now suggests the end date to be the 31st of March.

Can HR, on the basis of that, withdraw the resignation letter signed by me already and submit a new one with the end date of 31.03?

Hello Prabhat, thanks for your reply. The question is not about a good gesture but more about the legal side of things. Is a termination letter legally binding, or can it be changed without the employee's consent?

As mentioned earlier, the notice period is 3 months, and you have requested to reduce/shorten it. Now, the 21st of March and the 31st of March are just a fraction of days, and it may have taken place by discussion with upper management, above HR. However, the employee can challenge the change, but in that case, the reduction of the notice period may lapse, with some adverse effects on release. So, our advice is to proceed smoothly and take the release on the new stipulated date.