Sony India — Picture flickering

We had brought 46 inch tv and it was not working. We had got 49 inch tv by replacement company had given 1 year warranty and we have extended by 2 year by paying charge. Now the tv which we had got by replacement is not working in warranty period and problem was automatic on and off of screen. We had complained and complaint number is 59835186. Technision had come and changed the board. After change of board there was a green shade. Our problem was not solved and again the technision changed the board. After change in 2 days the picture started flickering. We had complaint in warranty period and our problem is not solved. To change panel kumta (Karnataka) sevice center they are asking charges. Please sove our problem.