unfortunately there is no email contact address for Virgin Mobile.
You could try the web chat: Contact us > Mobile > Your account > Chat online.
Otherwise you would be best calling. From abroad their UK support line number is: +447953 967 967.
Either way they will only post out a replacement SIM to your UK registered address. From there you will need someone to activate it (as I'm not sure you will be able to do this from outside the UK) and forward it on to you in NZ.
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