Rediff Shopping — Item when purchased was told buy 50 dvd and get 50 dvd free

I did shopping on Rediff. The item clearly mentioned buy 50 DVD and get other 50 free. Infact when i clicked on details it clearly mentioned that the item includes100 DVD. But when i got the delivery there were only 50 DVD, I have no idea what about the other 50 DVD. I feel cheated, i have already sent a mail to rediff shopping but i am sure they would not help, so launching a complaint asap so that i can get refund or the other 50 DVD.