Paytm Mall - Delivered used product

I bought a laptop from paytm on *-*-**** for my exams which are in next month (May). but paytm seller gives a used product which has an only *-month warranty. Then I bring this issue in front of paytm team with a proof of Hp official site. Paytm team rejected my case on the basis of invoice date and told use invoice for warranty. I told him warranty is based on the *st-time start of the laptop but they rejected my case.

Now I obtained a declaration from the hp department. In this declaration hp department mention that the seller gives a used system and same declaration, I have provided to paytm department * days ago but they are not providing any solution.
So I am requesting to you please solve my issue as soon as possible. I don't know why they are wasting my time. Now everything is clear from Hp department side.
I am requesting to you please solve my issue as soon as possible.
The important case number is given below:
*. Paytm reference no. is *********
*. Case with hp department  **********
*. Paytm order number **********