Axis Bank - Axis bank rejected my credit card fraudulent complaint

Four unauthorized transaction for Rs.***** is done on my Axis credit card on **/**/**** and **/**/****. I didn't share OTP to anybody and even I didn't receive transaction notification also in my registered mobile number.
I come to know about this transaction when I received my monthly statement on **/**/****. I blocked my card same day and registered complaint in customer care. All the required documents including FIR were sent to them.
Now after ** days of submitting all the documents bank people telling my request is rejected since card is not blocked within * days of fraudulent transaction taking place. Since I didn’t receive any transaction notification from bank I was unaware of this fraud transaction. As soon as I come to know I have blocked the card.
Now they have rejected this complaint stating the same reason “card is not blocked within * days of fraudulent transaction taking place”. But I have searched in their website and no where it is mention that card should be blocked within * days of fraudulent transaction taking place.
They have no answer to my questions.
*. How without OTP transition is approved?
*. Why I didn’t receive transaction notification in my registered mobile.
*. Why it took ** days for them to give this simple reason?
Please help me.