Carrier Air Conditioners - Complaining for leakage constantly occurring in AC

I have carrier AC from Khosla electronics at Uttarpara in November. We have used * Days only then it leaks the copper pipe. Then the technician came after * months and repair the leakage the AC is working correctly and then from after * month the technician came and tell the leakage occurred. Then they repair the leakage. After * month it seems to the same problem the AC doesn't give cooling technology and gives hot air from the AC. Then we call customer care and they sent a technician and they told me coil leakage in indoor machine and ISP panel * of are not working. They told me I have ordered it and they will come on * days then here * month is to be covered the technician doesn't come. I call the service centre and ASM Supriya Banerjee. They all didn't reply and doesn't receive a phone call. I would tell you that please step down and replace it we facing * months. When their summer season we have to use fan can't use AC. I kindly admire you to take a decision. Khosla electronic where I purchase dealer Partha Chakraborty misbehaving with me. Please resolve the problem that I have been facing. It's urgent.