Kent RO Systems Ltd - Kent Grand RO Fraud service and support

I bought Kent grand plus just *+ years now, since then I am facing lots of problem with this Dabba product, moreover Kent worst customer service agency from Wardha, Maharashtra is cheating and not providing good quality parts and service. Here are details about my concerns:
Since I purchase this third class product of Kent immediately after * months, I had to change some filter and sediment carbon basis on service agent advise and after that also mainly *-* months later I changed filter as per that agent advise, looking at high value machine filters and parts the service agent advise to purchase AMC, so on **/**/** I got * year AMC warranty from service provider and * months after that my filter motor was not working properly and giving some weird sound and filtering very less quantity of water, I made complaint to service agency but the customer support simply came and checked and said everything was good and no need to change anything as my product was in warranty that time and he dint changed anything despite of issue, after warranty over I made another service request for maintenance the service agent immediately changed the motor and filters. And I simply wasted my **** Rs of AMC charges for nothing, was it some sort of expected loot and fraud from Kent itself? Also in my absence the service agent changed filters with duplicate parts which supposed to get install Kent genuine parts, so from last * years I spent almost ***** Rs it means nearly **** Rs per year charges I paid so far and still don’t know how much additional I have to pay in future, as I was out of India could not able to follow up with Kent customer support and service agency and my parents those who leave in village they don’t know how to escalate this issue. In a span of * YEARS, I have already paid double the amount of the product price. Almost all the spare parts have been changed within * years of purchase. And the spare parts are available at sky rocketing prices. I regret my choice of purchasing Kent RO Water Purifier every moment. I want refund for all my money which I spent on this third class product.