Micromax service centre not returning phone since past 3.5months

I have a Micromax A116i phone.I bought it on 4th January 2014. Some problem started in it in the month of July 2014. It was under warranty period so i submitted it to micromax service centre on 11th July 2014 for repair. The micromax service centre details is M/S.Ananya Infotel,44 Shyama Pally, Jadavpur, Kolkata-700032. On that day they gave me a docket number E030489-071410703U78. They told they will return the mobile after some days. When they called next time on 27th August 2014 they told that they need some more time and gave me a new docket number of 914-11948620. But after that they never called. When i contacted them after 20 days they told they need some more time.When i called them again on 17th October 2014 they said they need to send the mobile to Delhi service centre as they can’t repair it. When i asked why they took so much time to decide this the customer service representative behaved in a bad manner and kept the phone down. I don’t know what to do. I am losing my hope of getting back the phone. Its already over 3 months my phone is with them. Please help.