Aakash Institute — Security Money

I was a student of Akaash Institute (Gorakhpur Branch) from my class 10th to 12th. So When I got myself registered in class 10th and 11th they charged security money which was to be refunded when I leave the institute. So last year I completed my 12th and also left the institute. So for the refund my Father went to the branch and asked for the same. The cashier there asked few details and told us that the money will be transacted back within a month. But it's been nearly a year, no rrefund has been transacted till now. Please help us get the refund back.