HDFC Bank — HDFC Credit Card - - Fault in actual transaction amount and what is shown in Transaction history

My issue is -

On 24th Dec 2021 I swapped my HDFC Credit card on an Indian Oil petrol pump with the amount of Rs 2904/- and received the same amount text message from HDFC Bank at the same time once the transaction was done successfully.

Now when I login online in my credit card portal there I saw a transaction of amount Rs 3005.06/- and got shocked because it is with the description of Indian Oil where I get the fuel with the same date of 24th Dec 2021.

HOW THIS HAS HAPPENED?
WHY THE TRANSACTION AMOUNT IS SHOWING DIFFERENT?

So now in reality I paid Rs.2904/- for oil purchase and the same message received from the bank but in transaction history it shows Rs.3005.06/- --- which gives a difference of about Rs.101/-.
Now I got a 1% surcharge back of Rs29/- in the card itself from the bank.

So now a big question arises --

Why is there a Rs100/- difference in the transaction amount compared with actual and what is showing online?

Please understand this question and even if you are not able to get this then please call me and I can explain to you in Hindi / English language (whichever is suitable to you).

Waiting for your call...

Also attached the text message and transaction history screenshots for your reference.

Regards
Rahul Goyal
M: [protected]