Based on your financial expertise, provide your response or viewpoint on the given financial question or topic. The response format is open.

PayPal wants me to “add a bank account”, another funding source. Credit card isn't working. Why?
Have you checked to make sure that your card isn't at the limit, or at risk of expiring soon?  Maybe PayPal has a policy to reject credit cards with expiry dates that fall within their buyer/seller protection periods? But to answer your question, no, I've never had this happen to me before.