I think that it's handled completely independent from Wirex (it may be handled by the bank though. Contis?).
It should have been asking first for set a password (obviously) - OR (!!) - the newer 3DS handling is done in many places by sending you an SMS to your phone with the code.
You have to do some major research to find the contis name and there's no one else to turn to in this time of need so that makes it Wirex's problem. They're the ones with their name on it. Still nothing from them.