The bare domain kristiandcross.co.uk has not been added as a custom domain to your Railway service, which is why Railway's edge returns its "Not Found" fallback page for it. Only www.kristiandcross.co.uk is registered on your service. To fix this, add kristiandcross.co.uk as a second custom domain on your Personal_Portfolio service, then create the CNAME and TXT records Railway provides for it in Cloudflare (with proxy enabled and SSL/TLS mode set to Full, not Full Strict).

For the www subdomain, verification has passed but the certificate is still issuing. With Cloudflare's proxy enabled, Railway sometimes cannot complete the Let's Encrypt challenge. Try temporarily turning the Cloudflare proxy off (grey cloud) on the www CNAME record, wait for Railway to issue the certificate (green checkmark in the dashboard), then turn the proxy back on (orange cloud). Once both domains are added and their certificates are issued, your site should be reachable on both kristiandcross.co.uk and www.kristiandcross.co.uk.