'This card is not accepted. Please use a different card.' means that Paypal are getting a denial message from your bank when you are trying to add the card. When you add a card or update the details Paypal charge a temporary amount. If this is not approved the card cannot be added. If you keep getting this message then call the number on the back of your card to check the issue with your bank. If the Visa you are trying to add is virtual or issued online you would need to try another card.
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