If you are using a PayPal account, please make sure that your shipping address exactly matches the address that you have on file of PayPal. An extra space or missing punctuation can cause the payment to fail. Once you have amended your shipping information, please try again. If you are using a Credit Card, please make sure that all credit card information is correctly filled in. If the verification fails, you can try again to see if the issue can be solved, or use another payment method. If payment problems persist, please contact PayPal. PayPal's phone number is 1-402-935-2050 (if calling from outside the US). You can also hit this link for help: https://www.paypal.com/gb/selfhelp/home
What happens if I'm charged twice?
Rest assured you have not been charged twice. Please contact your card issuer, as the money could be held by the bank.