Karbonn Mobiles — mobile fault sent to service but did not receive yet

Address: Tamil Nadu

Hi, my name is SULAIMAAN , I owned a Karbonn mobile phone ( model kt61) in february 2013. I was using it for a month then i faced some problem in my mobile like vibrating continuously for no reason and could not attend the call or swithching off suddenly then one fine day mobile displayed some fatal error and then it switched off i could not operate the mobile any more. since it was in warranty period, I searched for service centres in chennai. even called the customer support which revealed there are four service centre in chennai. i went to tambaram and egmore service centre who closed their service long before a year , finally i sent my friend to t.nagar to give the mobile for service he gave it there in T.Nagar service cente on April 1 and following them for the past two months they keep on postponing dates but i did not recieve the mobile yet. please help me out in getting mobile serviced or my money back i am really fed up of their product and service.