Micromax Informatics — Service center not returning my phone

Address:	713303
Website:	www.micromax.com

I had submitted my micromax GSM850/900/1800/1900.i purchased the phone on 12.02.2017. and the battery is just completely dead.The phone is in warranty period. i had submitted my phone in MICROMAX SERVICE CENTER in ASANSOL, west bengal.pin code-713303.They are not replacing the battery.19 days has passed.but they are not giving my phone back.i requested them several times to give my phone back to me.but they are not doing anything for this.micromax phone experience is very bad.and service center experience is very bitter.i request your head person please call that asansol service center employees and tell them to return my phone immediately.please take right steps so that i can get back my phone immediately.