The second charge that you see on your bank statement for one order is most likely an authorization (pending charge).

When making a payment by credit card for certain services, the card issuer may authorize your card before the actual funds are taken. 

If this is the case, the authorization appears on your bank statement in addition to the real charge, the authorization should disappear within a month.

Note: Each payment has only one transaction identification number. If you find there are two or multiple transaction identification numbers for one order, please contact us for investigation and support with the refund.