Kotak Mahindra Bank Credit card - Fraud Transaction

On Monday **nd November **** early morning at *:** AM IST received a call from Kotak Bank official checking whether I have made any payment to anyone internationally, I was shooked and traumatized as I haven't made any transaction to anyone and instantly I have checked my savings account and got shocked to see that my complete account has been emptied without my knowledge and permission of amount ***** has been transferred from my Kotak bank saving accounts to my own Kotak bank credit card account and I haven't shared any details like card number, account number, and OTP with anyone, and reaction to that without losing any minute I have checked my Kotak credit card account and found that fraudster has made a transaction of USD *** card less and without OTP and, to this, I requested bank officials to block all my bank channels and stop the payment immediately and block the payment and don't release the payment as I have informed the bank within * mins of happening that transaction and even the international payment needs time of **hrs for the conversation of amount from INR to USD but it’s all vain and bank didn't took the required action immediately and didn't try to stop the payment even I have given my consent to stop the payment instantly and inform about the fraud.
In the morning when the bank opened, I went to the Sector **-D Chandigarh Kotak bank branch to report fraud and given my written consent to stop payment and cancel the transaction done on my credit card. Bank took the request for my saving account unauthorized transaction and realize their mistake and reverse the payment which has been transferred from saving account to credit card account without my consent but on the other side, they didn't stop the transaction of USD *** equivalent to INR ***** approx and release the payment even when I have reported the bank within * minutes of happening that fraud transaction and send repeated emails and reminder about my complaint. Bank assure me that they are investigating and revert me back within ** days but it was all in vain, rejected my appeal and said it *nd level authorized payment and can't be reversed and I am liable to pay this amount, but every time I refused to pay as this is the fraud transaction and I don't want to victimize of this fraud transaction, now the question arises that for which International transaction the OTP is been required and verified by the bank as for all international transaction, bank authorizes the payment without OTP verification and that why all this fraud happens. I was then after a month getting repeated calls from Bank officials and third parties to pay the credit card dues and in a day they start making ** calls in a day and start torturing and harassing me and being a lady start threatening me that will take legal action against me, but I am ready to fight back as I have not done anything wrong and this is the clear cut case of fraud transaction. I am an old client of Kotak bank products and never be defaulted in my payment and all my previous payments were on time, so why this time I refuse to pay, as this is the fraud transaction done by some fraudster on my credit card and I haven't shared any details with anyone by any means and card and OTP was in my possession and never have been compromised by me, I was sleeping when this fraud happened on my account, fraudster very smartly first transferred the funds from my Kotak saving account to my Kotak credit card as if he/she knew about my credit card limit and then he makes the foreign transaction in USD and even the bank is unable to tell the beneficiary details which show the inefficiency of the bank and unable to verify the details about the beneficiary bank details and even if the bank don't have the power to pull money from fraudster account, then common man can imagine the kind of bank involvement and helping the fraudster.