HDFC Bank — hdfc credit card payment due date

I am supposed to pay the credit card due by 02nd of each month, which i have been usually doing on or before 01st of each month. Today 02 apr 2019 i am surprised to see an amount of 8305-00 is deducted from my bank account before even the business hours.
Is this not true that when a bank says on or before 02 or each month, the day has 24 hours and/or at the least till 4 pm of business hours?

I did pay the entire due amount of 63, 129-00 at 8:17 am. Could you please help me getting back the deducted amount of 8305-00?