L G Microwave
Automatic start after set timing

I brought lg microwave on 5 jan.2010. at GURGAON CENTRAL MALL.but that is not working properly, its start automaticaly after settle timer.its light blinks some times. In these three months 3 times the company engineer came but the problem is same.now i request u to change the piece and solve my problem.because i cant bare the visiting charges in future so change the piece.