You are not charged until the transfer is actually a success.

A pre-authorization for the total amount of the order is sent to the bank first.  If one is looking at an online credit card statement, this pre-authorization can appear to be a charge, but it's not an actual charge yet.  When the transfer completes, a charge is then sent to the credit card company for payment.   If it fails, we never send a charge against the pending pre-authorization request.

All banks differ in how long the pre-authorization stays on the card, but it will automatically be removed by the bank when they do not get a charge from us.  We do not have a way to force your bank to release funds earlier than their policy dictates.