Hero Motocorp — hero xpulse 200 engine opened

Address:

Mumbai City, Maharashtra, 400078

I purchased a new hero xpulse 200 carburettor on 8 th october 2019 from first day there was a unusual tappet sound i informed it to the dealer which is rydex motors located at nahur mumbai 400078.
They have opened my motorcycle engine for about 3- 4 times. They have changed the head. They also changed the scissor gear balancer pairs without my permission. The head which they have changed has cold shut marks on it which will not withstand high temperatures.
I am getting mentally stressed looking at the condition of the motorcycle and the way it is getting opened everytime. Its just 5 months ive purchased and the opened multiple times