Battery

I have bought a single phone and with only 4 months of use the battery exploded...i took the phone to game store where i bought the phone and they told me that there is no guarantee on the batteries and i accepted that...then i tried to buy a new battery but they didnt have it.they gave me the contact details of hisense to buy the battery from...ever since then i have been sending them email so i can get battery but not even one reply...this is frustrating because now i cant use my phone which is not even a year old...please assist me in getting hold of hisense so i can start using my phone again