I am also having the same problem a number of times. Sent email to Affinity, got a reply from Adam who said to check browser for latest version, I have done, tried different cards which gets me the same message. Made other purchase on other sites no problem at all. I also want to buy the version 2 package but unable to do so, so no doubt I will miss out on the deal before it is sorted. I do want to buy now but also in the future as well as in our present climate who can turn down income.
Please, please serif you need to sort this and for me it has only become a problem since the site revamp. It will be a shame to loose out on such good software and products because people are unable to buy.