Money paid but no product from company!

Location/place: Bangalore

Name of company/service: Pantel Technologies

I had pre booked and ordered T-Pad IS701R tablet through Penta’s site in march. They sent me a mail in may that the tablet is ready and that i should pay the amount for the tablet at a Punjab national bank. The immediate next day i went and payed the amount at the bank and from that evening itself, i sent penta a mail that i have made the payment.From that day till the 2nd of july i have been continuously sending them mails and calling them up.Finally on the 4th of July they call me up and tell me that the bank made a mistake in entering the UNIQUE REFERENCE id and so the tablet that u have paid for has been delivered to someone else and that THEY CANNOT DELIVER A TABLET TO US!!Even though we have payed for it and even though we have the challaan and all other proof. They say the Booking number entered by the bank was wrong but right below the number, my name M JUNAID ALI is there and my address and the address of the bank’s branch i have made payment is also there in the form and in the chalaan.Still they say they delivered the product to someone in PUNE and they are saying that they will not refund our money and not deliver the product to us either! Please help me file a complaint against them and get JUSTICE!