Nokia-6300
Flickering and heetgenaration

I purchased a nokia mobile phone (model no:6300) in the month of april. now it got flickering and over heet problem and Isubmitted nokia care centre vanasthali puram branch Hyderabad.they returned my ph on 12 -05 -09 and the problem was not rectfied . and I dont no what to do plese kindly help me in this problem.