Samsung - Service not provided

Item: Samsung Refrigerator
Model: RT**M****S*/HL
Samsung customer support team member called me at **:** pm on Saturday, May **, ****, just to inform me that the fridge cannot be repaired anymore after making me wait several days. She says that it is because of the third party service who messed up with the wiring system.
Why would I approach a third-party service in the first place if Samsung is capable to offer prompt service to the customer? Their service engineers are incompetent, lazy, careless and cannot offer solutions based upon the problems faced. Let me explain the matter of facts clearly in chronological order for your understanding.
March **, **** – I first contacted Samsung support team and they gave me the number of a technician from dynamic electronics, Budha Nagar, Peerzadiguda, Telangana. After making repeated calls to him he finally came for the first inspection. Hardly did he spend a couple of minutes he came to the conclusion that the problem is “gas got emptied”. How on earth could the problem rectification happen so quickly? Isn’t his responsibility to check all the units in detail whether there are any issues with them too? How could Samsung entertain such incompetent service engineers? Also, if the refrigerator stops working then the gas getting emptied is the only reason. God knows!
March **, **** – Another technician from the same dynamic electronics came to my home and refilled the gas. However, the refrigerator did not start working again like normal.
I started making repeated calls to everyone Samsung support team dynamic electronics and I was made to wait by them who kept on giving one or the other reasons such as attending a marriage ceremony or working in another location! Vexed up of their incompetent support, I approached the third party.
April *, **** – A service engineer from the third party company came and replaced fan and PCB. The problem did not get resolved still.
Tired of all these, I approached back their support team. Two people from Samsung came to my home and told that the wiring of the unit got damaged. They told me not to worry at all as they are senior service engineers and are capable of resolving the issues in any part of the city by attending calls round the clock! They whisked away by taking Rs. *** from me and promising that they will repair it on priority but only to return never.
Now, Samsung's engineers and support centre executives tell me that it is because of the third party engineer who messed up with the wiring system that the fridge cannot be repaired. How can they tell this? What were they doing when I tried reaching them for * month hopelessly? If Samsung engineers were able to find out the right problem and at the right time, then all these issues would not have happened.
I request you to resolve my issue immediately. Please don’t force me to take any major step against Samsung company and their service centre.