Billdesk — Payment debited, but not get receipt

Dear sir my name is ankit kumar and my mother name is indu devi and we are from patna bihar . i have made our electric bill payment on 18 may 2015 in morning through online payment mode by bill desk which is Rs.555. after completing my online payment process i did not get any confrimation report .when i updated my bank pass book then i saw that the amount Rs.559 is deducted from my account and pos no written of that transaction is[protected] .but when i contact to the electric department they told that your bill of this month is due. so kindly pls return this amount to my account as soon as possible.otherwise i have to take legaal action.
for further information or query pls contact to my number-[protected]or [protected]and my email address [protected]@gmail.com