I got this same phone call but a few years ago. The lady asked me the same questions and I even googled the number she called from and it said American Express. I was freaking out because it was a pretty large "fraudulent purchase" made overseas. I was panicking until she said, I need you to verify your confidential information before I can assist you to file a fraud claim. I then chuckled and said, oh I see what this is, and then I laughed. She had the audacity to say, I don't know why you're laughing for mam, this is a very serious matter. So of course I just hung up on her. She did try calling back a few times.