Sony India — Service center cheated me

Address:

Chittoor, Andhra Pradesh

Sir,
I bought sony xperia z1 mobile phone before three month's.
All the time its camera got hanged up.I went to the service center in tirupati, they have reinstalled the software many times.the problem repeated.so, they replaced a phone for me.
The same problem is repeating now also.the problem has become more.It is showing that camera is not available every time.l could not able to take a single picture.
The technician in service center cheated me.He replaced me a phone which is in worst condition than my mobile.
I have called to sony xperia call center several times.when ever i called them, they are saying that they don't have any information.
I HAVE THE ORIGINAL BILL'S AND JOBSHEET.I RECORDED ALL THE CONVERSATION WITH CALL CENTER AND SERVICE CENTER.
You can also contact me through my contact number :[protected](P.Naga Chaitanya)
Hopping the best and fast reply from you.
Thanking you in advance.