Hero Cycles - Faulty Bicycle Sold to me

My name is Debjit. I am from Kolkata. I bought a MTB from Hero Cycles from their store in Bentick Street Kolkata-** on */*/****. It had problems from day one on brakes and gears and its tube leaked * times in * months. The cause for the tube leak was for filling air in the tube by electric machine which they didn't warned me when I bought it and even when I went to buy the second tube. The disc brakes had become loose from the *nd Day of purchase and the gears had shifting problems. They sent the second tube to hero but no response drom them for * week. When I called them they said they had work and will call me back later. I asked for a replacement but they denied. The baddest cycle company. I want a refund since I don't want to have any relation with Hero.