Sony Xperia Miro Cell Phone — switch off issue during calling and call receiving

Address:

Gautam Buddha Nagar, Uttar Pradesh

Respected Sir,
I had purchased Experia Miro Handset from New Universal Office System,Greater Noida; dated : 22.02.2013. But the issue is while calling or call receiving, phone gets switch off. I took it to shop, where i purchased and discussed this matter. They told me to take it to Authorised Sony service center, registered with NRI Electronics, Greater Noida; phone no:[protected] on 30.04.2013. They told me that mobile service centre is in Ghaziabad and on 04.05.2013 i received my phone and checked and same problem persists. I took phone and submit the same to NRI Electronics. They told me the phone would be send to ghaziabad service center and their personnel will contact you about the problem and related feedback. Since, then i haven't received any call from their side. Besides i approached greater noida service centre twice, they told me that phone's PCBOARD needs to be changed and you will get your phone within a week by consulting ghaziabad's service centre official on telephone.They gave me phone number of ghaziabad's service centre's official named as Bhuwan whose contact no. is [protected] and i'm trying this phone but this person is not picking up his phone. There has been 11 days since i submitted my phone without any feedback on when i will get my phone back.
I need your immediate help on this matter as soon as possible.

Regards,
Ramandeep Singh Sidhu.