What is a 1018 Error?

A 1018 Could not find host in Cloudflare database error is a Cloudflare-specific error code for: "The domain points to Cloudflare nameservers, but is not registered or active in any Cloudflare account.".

How do I fix or troubleshoot a 1018 Error?

Common steps include reloading the page in your browser, checking for typos in the URL, verifying server status, clearing browser cache or cookies, and contacting the website owner or server administrator if the error persists.

1018 Error | Error-Message.Net

Common cause

The domain’s nameservers at its domain registrar are delegated to Cloudflare, but the domain has been deleted from its Cloudflare account, has not completed activation, or was deactivated.

Resolution:

If you are not the website owner:

The domain is pointing to Cloudflare nameservers without an active website behind it.

If you are the website owner:

Log into your Cloudflare account and add the domain back to your account.
If you intended to cancel Cloudflare, log into your domain registrar (e.g. GoDaddy, Namecheap) and change the nameservers away from Cloudflare back to your web host’s nameservers.

Source: Cloudflare Documentation - Troubleshooting Cloudflare 1XXX errors (Error 1018)