ANSWER
As with the majority of online retailers, once you have entered your payment details your bank will place an authorisation against that full order amount in your account. This will show as a pending amount on your statement but will not actually be taken by us.
We will only take money for the items that we send you and this is done when we have processed your order. Therefore, if we have had to cancel any items from your order, the money we take will be less than the amount which has been authorised by your bank and will be taken as a separate amount.
This is why in certain circumstances it appears that you have been charged twice for your order. As soon as payment was taken we would have automatically sent information to your bank to ask them to release any outstanding authorisation. This process will take up to 5 days depending on your bank's procedures. For orders placed from overseas this may take longer. Please contact your bank for details.