Paypal Payment Problem

Dear all: I just purchased cs cart professional recently.

And I set up my store and try to test my paypal paymend method.

And here is the strange thing happened: I add a item “Test” and set it price with 1 dollar, ID with 0001, quantity with 10 piece.

Then I use my real paypal account to receive money, cuz it only 1 dollar. and I just my own credit card to pay for it. The first time is fine, but when I run it by second time. Paypal showed me the error message when I tried to check it out.

""This invoice has already been paid. For more information, please contact the merchant.Return to Merchant "

And after no matter what kinda credit card I picked to use, it always show me this message.

Please anyone tell me how to fix this problem?

Hello cc8163,

The problem requires the investigation on your server. Please contact us via Customer Help Desk and provide us with a temporary access to your server.

Pavel Zyukin

CS-Cart Support team