The $1 charge that you see that is associated with your order is a pre-authorization charge. This charge can sometimes appear on your credit card, even when the order itself was cancelled, failed, or was rejected for whatever reason.
A pre-authorization is a temporary hold of the available balance on a credit / debit card and you are not responsible for paying for it. The hold is an action of the customer's credit card company, and we / FastSpring has no control over whether your credit card issuer decides to use this process.
The charge will drop off your card within 5-10 business days. The exact timeframe varies with each card issuer and each card issuer has control over when those charges will be dropped or voided.
This article was adapted from FastSpring's Support article on "why might a charge appear in the customer's credit card when the order failed."