There are two possible reasons for this: –
You may encounter a message after you have entered your credit card details and pressed BOOK NOW, ¨ technical error ¨ This can mean that the card you have used has not been validated/accepted. But often it can occur if you have been a long time in the booking process or have opened multiple browsers. Shut down all open browsers and clear the cache/history ( if you know how) and start again, preferably using a different browser. If after you have tried this is still does not work, try another card. Another possibility is your bank requires you to authorise the transaction via your banking APP or Bank website. As the transaction is not one, you normally make.