My cell phone was faulty but not replaced by HTC India office

Hello , I was an HTC cell phone user, I purchased the same with lot of hopes & excitement. It just 15 month passed and it has to visit your service center 3 times. Now HTC India service center is asking me 50% of the purchase cost for some repair that include the mother board. Any concern desk can check the reference of my earlier many complaines , my IMEI number - 356610012846867. I hope some one will take up this matter. From August 2009 the cell phone is at service center and many commitments given from HTC India office for replacement but its not fulfilled ever. Nirmalya Chatterjee-# +91-9833250138