Cars24 Services — Cancel the deal to Sell my car

Hi,
I got my car inspected and the offer was made. But I did not received any token amount. Now I have changed my mind and do not want to sell the car. The cars24 executive is asking for 1000 INR to cancel the deal, where as, I din not received any document mentioning the cancelation charges, neither I was informed that there will be any cancellation charges.

There is no customer care number available where I can escalate this.