The most likely explanation in this scenario is that our payment provider has blocked your payment because the address or ZIP/post code you entered does not match the address linked to your debit/credit card.
This is a common fraud prevention measure.
In this instance, your card has not been debited (even if it appears like it has), the monies are in limbo between you and us and will be returned to you imminently (if they've left at all).
All you need do to re-submit is visit this page and ensure that the postcode or ZIP code you enter MATCHES the address on the card you're using.
If you continue to experience problems even after following the steps above, please raise a support ticket and we will be glad to assist you.