Security management Toolkit 
Story: PayPal fights fraud with password key fob
Re: False Security
If this works the same way as the RSA system which I've used for some time, that cannot happen. If someone tries to log in twice with the same code it is logged as a security problem and log in is denied.
You can only log on using the code once, if the log on fails, you need to wait until the next code shows, and then enter using the latest code.
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