Tamilnadu Electricity Board (TNEB) — Double payment online

I have paid my bill amount of 977 rs on 29 march 2015, amount is debited from my bank account but in TNEB account it showed i have 977 rs bill pending. I tried after 2 days i.e on 1 April 2-15, this time amount is debited and also in TNEB account it showed nil balance.But I received receipt for those two payments in my email. I have attached the proof of transaction and the receipt with this complaint.Plaese kindly look after it and help me to get the money back..