Unless, of course, they've just typed in their 16-digit account number before being connected with you ;-) (Doesn't sound like your case, but people will miss

Unless, of course, they've just typed in their 16-digit account number before being connected with you ;-) (Doesn't sound like your case, but people will miss that little qualifier. I mean, of course, the cases where they ask for your account number - not verify details)