Airtel Xtream broadband - Delay in Airtel Fiber broadband installation by much more than committed time

I booked fiber broadband connection on ** Mar **** at **:** by paying **** via Airtel's official link. I met Airtel sales person Banti Singh (**********) in Adarsh Nagar Subhash Park and he was advertising there for Airtel. So, I called him and booked the connection and he assured that connection will be installed on same day i.e. ** Mar **** and after he left my home I called him in evening and he said it will be installed next day on ** Mar. I said ok. From ** Mar **** he is not answering call. I than called customer care and they said wait for ** hours as its timeline for broadband installation which is nowhere mentioned. Even in text which I got after making payment for * months says it will be installed in ** hours. Its been more than ** hours today on ** Mar **** at **:** IST and noone is willing to install connection. Now, I called Airtel *** for update for cancelling my booking and refund of Rs. **** they are saying server is down and call after * hours. Fraudsters. Please help me in getting my refund legally. Booking ID: **********.