Reliance Communications — bill without using

sir i am the post paid customer of reliance company my no is [protected] i was using it last year but so many problem occurring during payment of bill always they had given wrong bill. when i called to convert my plan from post paid to pre paid they not given proper response and guide after long time he gave me address and process to it. i go to reliance mobile store arya infotech sop no 14 A sri ram kunj east boring canal road patna on 20 oct 2014 i have paid my aall out standing till date र्‍र्‍s 675/- and given request for convert my no from post paid to pre paid but till date he has not given and sending me bill and calling me threating me to pay the bill which now lumsump 1000/-/ now on 99 may 2015 a company lawyer call me and threating me to come delhi court or pay the bill . sir give me favour i am so much suffring mental pain.. bill no is 1112 (i have bill copy)