Tata VSNL Broadband — disconnection and no response for 20 days after a lot of complaints

i am using vsnl broad band from a long time. i always use to face problems of disconnection and company rectify my problems in 2-3 days but this time i am facing disconnection from last twenty days and company is giving no response after a lot of complaints.vsnl company is asking for bill of that time duration when i havent used any internet connection and if i ask why my connection is disconnected they told me that you havent paid our bill thats why your connection is disconnected. now you tell me why i should pay the bill if i havnt used the internet.ph no.[protected]