Railway's nameservers (ns1-4.railway.app) only serve DNS for domains purchased through Railway, so delegating an externally registered domain to them causes every query to be refused and the entire zone goes dark. That is why nothing resolves even though the service itself is healthy.

To fix this, restore your registrar's default nameservers (or point them at a DNS provider you control), then add the two records shown for that domain in your service's Settings: a CNAME pointed at the target value shown there, and a TXT record at _railway-verify with the value railway-verify=62af8574583bfff3f3759649e8c19818b7b3c0712321fc2df1b9c0e7e07de3b1. Since this is a root domain, a plain CNAME is not valid at the zone apex, so your DNS provider must support CNAME flattening or an ALIAS/ANAME record. If it does not, you can either serve the site from a subdomain like www (which accepts a regular CNAME) and redirect the root to it, or move the zone to a provider that supports flattening. Our docs on adding a root domain list which providers support this. Verification and certificate issuance will resume on their own once both records propagate.