InFocus — automatic shut down of phone

Recently i purchased a infocus vision 3 from amazon... It is getting switched off automatically and then not opening... Even after charging it is not opening.. Then almost after nearly half an hour it is opening automatically... Also the phone is getting heated very much even after very less use... Its just been almost 3 days of purchasing the phone... I contacted the amazon customer care and they said me to return the phone whereas i just want it to be replaced with another new phone... Kindly help...