Non recovery of fraudulent funds

I got a what's app message and call saying that they will send me a gas cylinder. Hacked my phone and drained all the savings in my account amounting to Rs 2,59,673/-. I immediately reported it to the bank and the cyber cell authority. The police has also registered an F.I.R about the matter. The bank is not willing to co operate with me even though they know I have been scammed. No accountability or support from Kotak aside from adding to the grievance. Two amounts were credited back to my account but they soon got debited back by Kotak without any explanation. I need to do every possible legal thing to recover this savings amount. I have been provided with no relationship manager to assist me with the case. The nodal officers of the bank have also been sending me no solutions. Kindly requesting your kind co operation in this matter.