MTS Data Services, Wrong Bills, Over Charging and Miss behaving

I have Purchased a Data card of MTS (NO-8459232095) with post paid plan in 2015. In the starting everything was ok but in dec-2015 they charged me Rs 5.00 as Value added services. I ignored that Small Amount. Again they Charged me Rs 49.00 in Jan-2016 but i did not taken seriously after that for some months i did not checked the complete bill. as i received the message of Bill I deposited that as it was. But in Sep-2016 I checked the bill and found that Rs 255 were added in the bill in the name of value added service. I called up customer care of MTS they said this is for service activated by you. I said this is a data card not a sim and i did not activated any service so they said that they will deactivate the service and in next month I will not receive any Amount in the name of Value added services. The very next month in Oct-2017 I again received Rs 237 as value added services. I again did the complaint and said that last month i deactivated the services so how this time it came again.The Customer care Representative Mr. Mujiburrehman Apologized and gave me a request no (request number 3572833) for deactivation the value added services. Again in very next month in Nov-2016 Rs 243 Billed. Again i did complaint and their response was this (We sincerely regret the inconvenience caused to you.Further about VAS de-activation, we would like to inform you that we have registered a request to resolve the issue.The request reference number is 3602743. We will update you on your concern by 24-NOV-2016 by Ritesh Mahindra mts Customer care) But Again in Dec-2016 they again send me the Rs 231.00 in the name of vas. Now i was Fed up and again did complaint and their response was this(We sincerely regret the inconvenience caused to you.Further about VAS de-activation, we would like to inform you that we have registered a request to resolve the issue.The request reference number is 3613945. We will update you on your concern by 28-DEC-2016 by Ashok Kumar Vishwakarma mts customer care.) Again in Jan-2017 I received a Bill with Rs 255 as vas. I did Complaint again and received this response (We sincerely regret the inconvenience caused to you The request reference number is 3622361. We will update you on your concern  on 25-jan-2016.Further, we would like to inform you that as per the your request we have deactivate  your all vas services by Ashok Kumar Vishwakarma mts customer care) Again in Feb-2017 I received a Bill With Rs 240 as vas. Now i was Completely Out of My Mind and I did not paid them any Amount and when i checked all my Previous bills I found that they have already Overcharged me Total Amount of Rs-3404 from Nov-2015 to Feb-2017. In which they have adjusted the Amount of Rs 1221 and still my Rs 2183 is on their side which they already Charged with me. Now they are Compelling me to pay the Bill Of Rs 1666 and They always misbehaves on Call and gives Threat by Lawyers Phone from Court and sending me legal notice from Court. One day they Did 40 calls on my phone to pay the bill after picking up the phone their representative said bach ke kahan jayega tu. they Discontinued the service their Dongle is also Lying with me use less which i have also paid Rs.2000. Kindly Advise me What to Do and how to deal with these Peoples. Daily they Call me and Gives Threat i have gone mentally upset. Please advise me.
Thanks
Vasim Ahmed Siddiqui
MTS no-8459232095