No, that's not an error. An error is something that is incorrect. This is correct. Not all cards can be used with PayPal. This card cannot be used with PayPal. You can use this card in person, in a real store, where they scan it in their machine. To use PayPal, you have to use a different card.

Any number of reasons.

In this case, paypal SAYS its their error so try again later.

Let me guess, it is a prepaid card.

No

Make sure it is not out of date, and that the card is valid for PayPal transaction.

Yes

It might be a paypal error, or it could be that your card company has not made an agreement with paypal, meaning that you can't use that card.