WHIRPOOL INDIA - Faulty Refrigerator

I purchased a refrigerator (Whirlpool ***L Intellisense Inverter * Star) which is still under warranty and as per company suggestion purchased extended warranty cum AMC from whirlpool too. From last one year refrigerator not working satisfactory / cooling and informed customer care. On complain they sent technician and do some repair work but situation not improved. They changed some part too and informed it not cooling as stabilizer not there and forced me to purchase their stabilizer (around Rs ****). But still no improvement in refrigerator cooling, now they are saying it has some fault which is beyond repair so they will replace refrigerator with new one but i have to pay for differential amount. Differential amount informed is Rs *****. This is unacceptable as product is under warranty and i purchased their AMC which is still valid. On my disagreement they are offering me proportionate amount of AMC for remaining period of AMC. I am bearing this faulty product from last few years and raised multiple complain. Purchased refrigerator for Rs ***** (after credit card discount) and purchase their AMC and stabilizer (although of refrigerator it did not require). My grievance is not high differential amount, product is under warranty and AMC is not expired. either repair product to satisfaction or replace it with reasonable differential amount