There are several reasons for unexpected charges:
Small charge of approximately 1 US Dollar or 1 Euro: Likely a temporary authorization to verify that your card or account is active, which will automatically clear from your statement. Re-check your statement after several business days.
Full order amount charged more than one time: Your statement may mistakenly display the order twice or display the completed charge and temporary authorization separately.
Two or more completed charges: To request a refund of a duplicate charge, contact Support through this link.