This could be for the simple reason that your postcode is not yet registered with the Royal Mail address database. To search or register your address, please go to the ‘postcode finder’ application on the Royal Mail website.
To make a train booking, your address will need to be manually updated on our system; you can do this by emailing your address to our web support team at contact@c2crail.co.uk, or by calling 0345 744 4422 and selecting option five.