Un authorized transaction in GOOGLE+0ctro

On 07-05-2017 at 5.50 PM , i received a message, that a charge of USD 77.73 has been initiated on your RBL Credit card at GOOGLE+0ctro inc, which i have not initiated. Then i called customer care at 5.58 PM and asked to cancel the transaction. I informed him that i have not received any OTP and i have not done any transaction.I enquired about how transaction done with out OTP, he replied that for Dollar transaction OTP not required. I have not done transaction and so please cancel that transaction.