LEMP stack restarting error

Comment one directive. You have both uncommented. just do this as mine:

# pass PHP scripts to FastCGI server
        #
        location ~ \.php$ {
                include snippets/fastcgi-php.conf;
        #
        #       # With php-fpm (or other unix sockets):
                fastcgi_pass unix:/var/run/php/php7.2-fpm.sock;
        #       # With php-cgi (or other tcp sockets):
        #       fastcgi_pass 127.0.0.1:9000;
        #}

        # deny access to .htaccess files, if Apache's document root
        # concurs with nginx's one
        #
        location ~ /\.ht {
                deny all;
        }
}

As it says, you got the fastcgi_pass variable two times in your configs. Remove one of em.

Open your /etc/nginx/sites-enabled/default and find fastcgi_pass you have written two times. remove one <br>Example <br>location ~ .php$ { <br> fastcgi_split_path_info ^(.+.php)(/.+)$; <br> # NOTE: You should have “cgi.fix_pathinfo = 0;” in php.ini <br> <br> # # With php5-cgi alone: <br> fastcgi_pass 127.0.0.1:9000; <br> # # With php5-fpm: <br> fastcgi_pass unix:/var/run/php5-fpm.sock; <br> fastcgi_index index.php; <br> include fastcgi_params; <br> <br> }