LG Electronics - Refrigerator defect not repairable

I have purchased one LG double door refrigerator in ****, in which lower part was not cooling. So I raise complaint through customer care to rectify the same. LG service engineers attended the complaint one by one and changed various parts (as an experiment without finding the main issue), which cost me Rs.****/-. Since the machine didn't rectify, I escalated the issue to LG CEO & MD, still the issue is not yet resolved. I am following up since Nov'** for the same. At last they take away the refrigerator to their service station for thorough check up and declared this unit is not repairable. They are now offering **% of the cost, which is in their approval, don't know when will receive. My complaint is if the issue is not repairable, then why LG service engineer changed other parts and cost me ****/- , so I now demand a new refrigerator in replacement or **% of the unit cost plus ****/- to be paid by LG. If required, I will share all complaint no and money receipt no through which I have paid ****/-. Please help.