Infosys date of joining and notice period overlap, can DOJ get extended by team?

My DOJ is 29th Dec 2025 but received the offer letter on Oct 6th 2025. I have 90 days of notice period and its getting overlapped. In my case he's saying he will extend the DOJ in the month of December 2025 itself.

He's not willing to change the date now but rather saying the same thing like to resign and provide the resignation acceptance email or LWD document to consider the DOJ extension.

Please help me......