Citibank — 6 unauthorized transactions on debit card

Address:	New Delhi, Delhi, 110001
Website:	citibank.co.in

6 unauthorized transactions - total inr 1, 41, 800 were made from my debit card details. I got sms from citibank reg these transactions. I am in us and my debit card is very much in my possession. I didn't receive any otp for these transactions. What kind of security is citibank providing to its customers bank account details. There is no pre authorization like otp done on transactions. Citibank should contact the customer if payments of this hight amount is made from an account. I want a reversal of these transactions immediately.