Sony India — Change my Phone parts

Address:

Ghaziabad, Uttar Pradesh

I give my phone Model No C6602 Mobile No. W[protected] to the Sony Service Center NO.1, DAYANAND VIHAR, VIKAS MARG EXTENSION New Delhi-110092 for repairing ( This set is fully working condition with earphone insertion with out earphone it make mistake to hearing voice) . They ask me for depositing Rs. 4800/- to repairing my set but I thought that they ask me too much to repair. I decided to take back the phone and give to the FI INFO SOLUTION & SERVICE PVT LTD Cannought Place Delhi - 110001. They ask me on phone for Rs17000?- for repairing. but the original cost of this phone is not more than 20000/- so I get back this phone and give my friend who give it to some known person he is working in the Sony company. This time company declared dead this phone. what i can do? in this position. please suggest.