Samsung — unsatisfied with service center

5 days before in my home i was charging my samsung mobile phone (s7562) and after sometime when i checked my phn was off and there was some burnt smell ........but my mobile was working fine and aftr sometime i plugged again but it didnt charge so i went 2 the samsung service centre and showed it and they told me that the circuit has burned and the motherboard needs replacement and 3000 rs would be the cost ... so its within warranty and its not customer fault for this type of failure .... my mobile is 3 months old .... if it turns out like this why the hell should i pay money for .... so please kindly look into the matter and reply me asap ....