(Would they be blocked after some error messages but not others?)
User’s should receive an error message if the payment is not successful and should receive the option to re-enter the payment details. If the card details are wrong/missing, the user should have indefinite number of attempts. If the issue is with the card itself, the user can be redirected to a page were the reason is provided (for example, refused due to insufficient funds). But these are not actually error messages, but responses to the payment.