NGINX SSL证书激活失败问题求助

各位大佬好，我最近在VPS上给域名artnbud.com配置SSL证书时碰了壁——照着步骤操作完，证书始终没法成功激活，折腾了好多次都没解决，来这儿求大家帮忙看看！

先贴一下我当前的Nginx配置文件内容：

server {
        listen 80 default_server;
        listen [::]:80 default_server;
        #server_name artnbud.com www.artnbud.com;

        # SSL configuration
        #
        # listen 443 ssl default_server;
        # listen [::]:443 ssl default_server;
        #
        # Note: You should disable gzip for SSL traffic.
        # See: https://bugs.debian.org/773332
        #
        # Read up on ssl_ciphers to ensure a secure configuration.
        # See: https://bugs.debian.org/765782
        #
        # Self signed certs generated by the ssl-cert package
        # Don't use them in a production server!
        #
        # include snippets/snakeoil.conf;


        root /var/www/html;

        # Add index.php to the list if you are using PHP
        index index.html index.htm index.nginx-debian.html;

        location / {
                # First attempt to serve request as file, then
                # as directory, then fall back to displaying a 404.
                try_files $uri $uri/ =404;
        }
}

我已经确认了证书文件的路径是对的，也重启过Nginx服务，但就是没效果。想问问大家，我的配置里有没有漏掉什么关键项？或者还有哪些排查方向我没考虑到？麻烦指点一下，谢谢啦！

备注：内容来源于stack exchange，提问作者BangoChain