sk-cargo.com’s server DNS address could not be found.

After adding sk-cargo.com under networking menu, I still cannot access via this URL, set up also done in nginx, other domain can but sk-cargo.com not. what can I do?

server {
    listen 80;

    server_name sk-cargo.com www.sk-cargo.com;

    location / {
        proxy_pass http://...my digital ocean ip...:3000;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection 'upgrade';
        proxy_set_header Host $host;
        proxy_cache_bypass $http_upgrade;
    }
}

Also, in nignx.conf I have enabled this command…

server_names_hash_bucket_size 64;