How to install Premium URL Shortener in ISPConfig with NGINX

I'm having trouble installing premium-url-shortener in Ispconfig with NGINX.

I don't understand if I'm doing something wrong or if ISPConfig is to blame.

I'm an ISPConfig user since 4 years, but sometimes I get confused by some mysterious errors.

This is the documentation for premium-url-shortener:
https://gempixel.com/docs/premium-url-shortener

This is the NGINX directives setting I added in ISPConfig.

Code:

server {
    listen 80;
    
    # MAKE SURE THE DOCUMENT ROOT IS THE /public IN THE FOLDER WHERE THE DOMAIN POINTS TO (required)
    root        /var/www/clients/client1/web78/web/public;

    add_header X-Frame-Options "SAMEORIGIN";
    add_header X-Content-Type-Options "nosniff";

    index index.php;

    charset utf-8;

    ## SAMPLE REWRITE RULE FOR THE SCRIPT (required)
    location / {
        try_files $uri $uri/ /index.php?$query_string;
    }

    ## 404 ERROR (optional)
    error_page 404 /index.php;

    ## THIS IS JUST A SAMPLE, IT WILL DEPEND ON YOUR SERVER
    location ~ \.php$ {
        fastcgi_pass unix:/var/run/php/php7.4-fpm.sock;
        fastcgi_param SCRIPT_FILENAME $realpath_root$fastcgi_script_name;
        include fastcgi_params;
    }

    location ~ /\.(?!well-known).* {
        deny all;
    }
}

I see only a white screen. Can you tell me if I did something wrong?

 

Of course. You cannot overwrite server {} via nginx directives.

 

Sorry, but I didn't understand.

 

Thanks!