Double charges shown on your online credit or debit card statements are the result of either an AVS mismatch error when processing your order, or an "edit" to your order done after you have processed it.
If an AVS mismatch error occurred, your card-issuing bank or credit card company puts a hold or pending charge on your account to cover the purchase amount of your order. The funds will then be removed from you account. However, your card was not charged. Your credit card company or card-issuing bank will return the funds to your account, typically within 2-3 business days. If you have questions regarding when the funds will be released back into your account please follow up with your bank or credit card company.
If you make an 'edit' or change to your order, the first transaction will be voided and your items will be placed into the shopping cart for you to make the desired changes. However, your credit card company or card-issuing bank may still place a hold on the funds for your first order for up to 5 business days. This can appear as a double charge on a online statement, but your credit card company or card-issuing bank will release the funds back into your account. If you have questions regarding when the funds will be released back into your account please follow up with your bank.