Refund of mobile no recived yet.

Location/place: pune

Name of company/service: student

I have purchased a blackberry strom 9530 on Oct ’12 from “rediffshopping” of amount 7123+(500 courier charges) the product was faulty and used. After five replacements, they send another blackberry strom 9530, which was also used and faulty.
On 22nd Feb’13, i applied for reund proccess, and they promised the proccess will be complited wihin 15 days, but still I did not recived the money.
Please take some action and help me to get the money as soon as possible