problem - earspeaker problem

Dear sir/mam
I have purchased Sony Erission Mobile Vivaz Pro u8i on 25/09/2010 and it is still in warranty. I was facing earspeaker problem. I had given it to ACCEL CARE CENTER, ECCELENZA SERVICES PRIVATE ltd. 204-205, 2nd floor, MADHUBAN BUILDING, NEHRU PLACE NEW DELHI-55,Sony Ericsson Authorised Sevice Center on 30-05-2011 but till date 12-06-2011 they did not repaired my cell phone. Many times i called and ask for the cell phone status but they said to me every time that we don't have that particular part of your phone and how much time will it take ..now you are requested to suggest me what should i do
I want immidiate action on this ...

Mohit Sharma
My Email addres- sid_dk25@yahoo.com
MY Contect No- 9968706470
Workorder No- SE31147110412
IMEI NO- 012305001108454
Model- Vivaz Pro u8i