Irctc — Booking of tickets

Address:

Mirzapur, Uttar Pradesh

I would like to mention one thing that I booked three tickets from allahabad to ahmedabad for 13th June 2015 in Patna Ahmedabad SF Premium Special Train. I booked my tickets last week and the availability was 290 seats at that time, when I was redirected to the payment page it showed me rs. 4720 per person and when I am checking the status of the train which is going to depart on 20th June 2015 the availability of the seats are 207 and it's showing rs. 3055 per person. I want to ask you why I have been charged so much? Please solve my query because I feel like I have been cheated. My pnr is [protected]