Please make sure your card is authorised to be added to online marketplaces. Some banks have strict restrictions on this and require you to authorise this over the telephone. Please also check your online banking app to ensure there are no pending authorisations that are stopping you from adding a card. Car & Classic uses Stripe, a globally trusted partner, to handle our card payments. In most cases, double-checking with your bank solves the problem. If your issue persists, please reach out to auctions@carandclassic.com or support@carandclassic.com