Consumer Redressal

I purchased Samsung Galaxy S4 on 27th Dec 2013. Few days later visited service center for software update and from the same day I started facing battery backup problem. I visited different service center and they said motherboard is damaged. They replaced it but I still faced the same problem. Again visited service center and they updated software version. But I am still facing the problem. Within 3months I visited service center 4times. Samsung is now denying to replace the device. The people at service center damaged the phone and they even did not record a entry when I submitted my phone. Kindly help me so that I can get a new device. Samsung is trying to cheat customers. I have even talked with senior representative and they told me to visit service center again. But this is wastage of time. How many times will I have to visit service center and they can\'t even rectify the problem and on top of that saying that its not a problem. Expecting kind cooperation from your side.