If you see two identical charges (down to the penny) in your online statement, one of them is probably a temporary authorization as opposed to an actual charge or debit.
Although authorizations aren't charges or debits, they can reduce the available balance in your account for 24-72 hours (the exact time frame depends on the individual bank or credit card issuer).
Contact your bank or credit card company to dispute a duplicate authorization if you wish to remove it before the 24-72 hour drop-off period.
On the other hand, if you see multiple charges on your paper statement or you're not sure what they're for, please contact us for assistance. If possible, have your order or confirmation number handy.