When using the PayPal option, there are some CC that are not being accepted?

Many of the Credit Cards work using the PayPal payment option but there are some that don't.

Any ideas??

PayPal accepts all major credit cards from Visa, Mastercard, American Express and Discover. If you find your credit card is not being accepted with a message such as "The card you entered cannot be used for this payment. Please enter a different credit or debit card number."

Your card is associated with a specific PayPal account, and you're not logging in with that particular account.
Your card was associated with a PayPal account that has since been closed.
You've linked the card to a PayPal account, but have not yet confirmed it.
You've exceeded your card limit with the PayPal system.
Your email address is raising a red flag in PayPal's system.
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