In case your payment by credit card should not work, please check if it depends on multi-factor authentication on the credit cards you are using. As a solution, we suggest making the payment via PayPal. In this regard, you might take a look at the short guide available here. After accessing the payment methods page, choose the last one; Select "Banca Intesa" connected with PayPal, you will be directed first to a payment page and then, after checking the checkbox, to the PayPal login page
