quicknow.in – dublicate product sending but not refund cash

i ordered one mobile online blackberry z10 price of 4999 the date of 9th november.the website is quicknow.in they are sending china mobile worth 750 so return the product return address i will refunding your amount with in 24 hours promise me i am also return the product but still not refunding amount calling time also not pickup any call so kindly take the action this company