Delhi Jal Board — Partiality in sending water bills/average bills

My K No is [protected]. Water connection installed at my residence in May 2012 and since than average water bills have been received without mentioning status of current/previous meter Read. Now I have recd bill No[protected] dt 27 Mar 15 stating current meter read status 729. My complaint is who is responsible for sending average bills to me since May 12 to Mar 15 inspite of Meter is installed at my house?. I have paid all previous bills total amounting Rs 8146 till date. What are the charges for consuming 729 KL? Moreover, there are so many house in my locality and nearby my house who have not taken valid connection and no water bill is asked from those houses. Who is responsible for no sending water bills to these houses? What action will be taken by DJB against these Water thieves.