Exactly what was the error message you get from PayPal?
Do you mean that you can not use the card to make a purchase or can you not even add the card and complete the verification process?
What type of card is it that you are attempting to use?
If it is a debit card, do you have enough funds in your bank account? (PayPal will charge £1.50 for verification when adding the card), and also PayPal will make a £1 temporary charge to check if you added correct card information. So you will ned atleast £2.50 available in yoru bank account to add and verify the card.
