I'm aware of this error happening for no apparent reason, it happened to me when XIV's ftp period was over. SE blamed the bank, the bank blamed SE, I resorted to prepaid game cards, emailed SE a photo of my Visa, nothing was resolved. Quit XIV and came back to XI and used the same damn Visa to reactivate my XI account without any issues whatsoever. SE really needs to fix this asap, it's ridiculous the amount of hoops they want us to jump through to be able to pay them.
My previous post was in response to someone apparently claiming you will get this error message if the credit card and the SE account are located in different parts of the world. Like I said, I have used my EU Visa to pay for an NA account (NA SE account too) without any issues for over 2 years.