Flipkart — vivo v 15

I have order vico v15 on 15-oct and it has to delivery on 19-oct but till 25-oct it is no delivery. I have called to flikart so many time there not able to give the information and they tell it will come on 22-oct after 24-oct. I was waited t ill 25-oct no body as resoling my issue so i have cancelled my order, they told it will refund more than 15-day but that also not sure. They did fraud transaction with customer money and not able to resolve the thing. Please anyone help how to raise the complaint on the same to get my money 14500/-