Hello Klaus,
Please make sure to choose your country in the PayPal form, and enter your address correctly.
If you get this message:
“The card you entered cannot be used for this payment. Please enter a different credit or debit card number.”
… this means that you have a PayPal account that has not been used by you in a long time and in which you have used the same credit card. If this is the case, log-in to PayPal instead of paying with your credit card.
– admin