Billdesk — charged for paying bill

Address:

Ashok Nagar, Hyderabad, Andhra Pradesh, 500084

I paid my bill on TSSPDCL online bill desk via debit card.

Bill amount is INR 3535
I was debited INR 3572.47

When I initiated the payment I typed the correct amount.
When I received a payment confirmation from the bank the amount was different.

Can someone help me understand why I was charged more than bill amount?

USC:[protected]
Bill month: May 2019