Samsung galaxy tab 2
Not refunding the amount

Sir,

i had purchased samsung galaxy tab 2 order no 10298960 on 31-07.But next day i had cancelled this order bu sending mails and calling to care center. But till date they have not cancelled my order and not refunding my amount, It is also showing in order history awaiting for shipment till date.they are also not refunding my amount. Now tell me what i should do...