And my point is that it is blindingly obvious. Someone rang you up stating they were from a bank and asking you for information. That is about as obvious as it gets. If you found it more believable because of her accent then I would strongly recommend you spend a little time protecting yourself in the future by reading up on common tactics. Basing your fraud detection on accents and line quality is, sorry to say, extremely naïve.
When working in the back office of one bank in 2001-2001, this scam was known then. There's nowt new about it.
We always said to customers that if they didn't trust the call to them, hang up and call either the telephone number on the letter, or the telephone number on their card, if they had one on the account.*
Some accounts were purely online, others had no cards on them. I still have the staff fraud office number on my handset.
All access to an account was marked by the system, time, date and who. Available to the fraud office in almost real time. Making any false calls stand out due to no account access/activity showing.
*The other option given was to take the letter into any branch. Issuing office of the letter is in a code amongst the reference number.