Voltas — product issue

Address:

Tilak Nagar - 110018, Old Shahpura

Facing gas leakage issue in 1.5 ton window ac almost every year. Last year only, they checked & filled the gas & this year again its same issue. Pathetic customer service. Its almost 6 years that i have purchased this ac & almost every year, i face one problem after another.
Every year we log a complaint and service engineer re-fills the gas identifies the problem with a component replaces the component and promises us saying that this issue would not repeat again. However, the issue repeats after couple of months. Once the service engineer changed the coil outside saying the gas is getting leaked from there. Next time they changed some pipe, next time they said the gas is getting leaked inside so they took out the coil and performed soldering after that they did the same thing again with the coil.
I don't understand that how many times a issue should repeat to identify the problem and fix it. If it was first or second time then i would not even taken the pain to search for this forum and log a complaint. But this is 4th time we are facing the same issue.