Prestige — repair in top glass 4 burner gas stove

We bought the top glass 4 burner gas stove 4 years back, till 3 years its functioning was good but in the 4th yr there is a problem in the fame of the burner. We contacted the service center thus a person attended the service in our home and checked the gas stove and said that there is a repair in the burner n it has to be replaced. He has taken a service charge of rs.250/-. He checked it on 28th july till now means december there is no service. They didn't even called us and even the service center in our town i. E., kakinada is very inefficient. The workers are not at all paying attention towards customers problems. Moreover if there is any repair in the parts of any products then those are not even available after so much of searching too.