Irctc — Needed Refund for Failed Transanction Id-[protected]

Hi, On december 3, 2014 I booked a ticket for 2 passenger for super ACExpress Train Name:12624/CHENNAI MAIL and I made an payment through HDFC netbanking. Later on When I checked PNR status understood that ticket is not booked. Some transaction failure occured. I dont know how it happened, Even amount from my account was deducted around 2500. So I waited for refund for 1 week, still my amount didnt got refunded. So please do necessary steps to rectify problem