this is answer from administrator paypal for this problem :
Hi andreea,

Ok, that information definitely helps. Thank you!

What's happening is that the specific card you have on file is being ruled out. This can happen for a number of reasons. It could be the merchant doesn't accept that type of card, or it could be an issue with validating the card with the bank, or it could be any number of security factors that cause our security models to rule it out for that transaction at that time.

The system is offering you the ability to use a different card to complete the transaction, but you can't put the same card's information in there, only a different card.

I hope that helps!

Olivia