IDBI Bank — fraud transaction from my debit card

Address:

Mumbai City, Maharashtra, 400098

I Aisha Javed Kazi, holding a saving bank account in IDBI bank of Kalina (Santacruz east) branch. My Account no. is [protected] and my Debit card no. is [protected].
On 23rd April, 2018, I got a call from number [protected] from an Individual (Kuldeep Sharma, Customer ID[protected], he said to me that he is an IDBI bank officer. He gave me my over all account details i.e My account nos., My Bank branch, My Debit card nos. My nominee details and My current Cash at bank. He said that because of some reason IDBI has blocked my debit card which is essential to be renewed. H e also asked me to share a OTP nos which he has generated to activate my debit card. After sharing an OTP nos with him, I have lost Rs.4500 from my account. Again he called me up and said new OTP has been generated which is essential to reverse an amount, in this way after sharing an OTP for second time I have lost my remaining Rs.800 also from my IDBI bank account.
How can any individual can have such an accurate details about an Account holder that how much Cast is at bank? Who is the Nominee? Debit Card details, etc.Unless some one form bank department provides same...
I have also lodge police complaint against this fraud on 23rd April, 2018 at Vakola Police station (santacruz east, Mumbai) I am attaching the same.