Tamilnadu Electricity Board (TNEB) — problem with my meter reading

Address:

Chennai, Tamil Nadu

Dear Team, my service no is [protected] name & address (R.Mythili 11/A teachers colony 2nd street kodungaiyur) we are tennet to the above mentioned address for more than 2.5 years.We never got this much of Electricity bill and We were not at all using the power in the day time . Then i dont know how we got 400 units the amount is showed Rs.1030 for March month 2015. our usage is very low then how is it ????. This is with the reading problem so, Kindly take necessary steps to sort my problem ASAP.