Vodafone India — payment for disconnected postpaid number

I have submitted a disconnection request on 19july2017 for my postpaid vodafone number in vodafone showroom... After 2 months now bill generated for the same number. When i approached vodafone showroom again they simply said some one from vodafone team has activated. I don't know without my confirmation how they activated the same number. Now the bill has been generated and they requested me to pay the bill..

I didn't ask them to reactivate the number so i won't pay the bill...

Note: for closing the post paid connection they are asking us to visit the showroom and write the letter for closing reason but for reactivating the same sim no again why they are not asking any confirmation from the customer end?