Blue star india - Replacement of Window AC under Warranty

I had a good repo of the Blue star ac company thats why I and My friend Dr Nafis Ahmad bought a new * star Window ac * months back. it was used for * months at that time. When I started it this season its cooling was very low and within no time it stopped cooling. While the ac of my friend is working nicely. I complained for it and the company men came and told that gas is leaked.
How it is possible that gas is leaked in * months. while previously I used a LG window ac which continuously worked for more than * years without any complain.

there are * possibilities of gas leakage-
*. There was a very very fine failed seal (joint was not proper) at the joint through which the gas is leaked in long duration.
*. The Low quality material was used at the joint which corroded within few months and gas is leaked.

In both of the conditions there is a fault of the company, means manufacturing defect.
Now I am asking company to replace my ac as it is under warranty and they are insisting to repair it.