The server could not resolve the requested hostname. This typically occurs when the domain is not configured in Nginx Proxy Manager or the DNS resolution has failed.
Verify that the hostname is properly configured in your Nginx Proxy Manager dashboard and points to the correct upstream server.
Ensure your DNS settings are correct and the domain name resolves to the proper IP address of your Nginx Proxy Manager instance.
Review the Nginx Proxy Manager logs for detailed error information and troubleshooting guidance.