I have just been the victim of a banking scam so wish to make people aware to prevent from suffering the same experience.
A rogue payment request was made on my credit card, for far more than my credit balance. I then received repeated calls from a private number but then decided to answer as I wondered whether the call was from my credit card company to advise me of this payment request.
The caller was well prepared, professional (though direct) and used passcodes to "prove" that he was legitimate so I decided to follow their advice on dealing with the matter in hand. Then things got out of hand by which time it was too late.
They are very clever people and know precisely how to use psychology to get what they want.
So, having become a victim, I plead with anybody reading this message that if you do receive a call like this from somebody acting as a member of your bank's fraud team, or indeed any other department, always ask them for their number and then phone them back.