A phone call

Today I got a phone call from 855-xxx-xxxx, it was a man claiming to be from VISA Group Service Center:

Me: Hello, what’s the issue?
Him: We found two abnormal charges on your VISA card today and need check with you.Please tell me your name.

Me: So you don’t know my name?
Him: We know your name, but we need to make sure it’s you and not someone else holding this phone.

Me: Ok, which bank issued my credit card?
Him: We are from the VISA Group, we handle all banks’ VISA cards, including RBC,CIBC and TD.

Me: What’s the last 4 digits of my card?
Him: I cannot keep doing this service, Goodbye.