プレビュー部分でパスが合わないのが罠でしょうか

server {
    listen       80;
    server_name  {server_name};
    root         /var/www/vhosts/fc2blog/public;

    index        index.php index.html index.htm;

    location / {
        try_files $uri $uri/ /index.php?$args;
    }

    location /admin {
        try_files $uri $uri/ /admin/index.php?$args;
    }

    location ~ \.php$ {
        try_files $uri $uri/ /index.php?$args;

        fastcgi_pass   phpfpm;
        fastcgi_index  index.php;
        fastcgi_param  SCRIPT_FILENAME  $document_root$fastcgi_script_name;
        include        fastcgi_params;
    }

}

関連記事