Can't see node STRAPI CMS application from outside - ERR_CONNECTION_REFUSED

Question

I tried to run STRAPI CMS on my VPS.

App runs via PM2 and internal curl is ok, I see response from app

curl -v http://127.0.0.1:1337

But external curl is problem, nowadays I want to access just it via http://89.221.222.178:8090 (just for testing before switch to "domain mode").

curl -v http://89.221.222.178:8090
* Rebuilt URL to: http://89.221.222.178:8090/re (v6)
*   Trying 89.221.222.178...LLOW       Anywhere (v6)
* TCP_NODELAY set          ALLOW       Anywhere (v6)
* connect to 89.221.222.178 port 8090 failed: Connection refused
* Failed to connect to 89.221.222.178 port 8090: Connection refused
* Closing connection 0
curl: (7) Failed to connect to 89.221.222.178 port 8090: Connection   refusedata.poutnicesty.cz

Firewall allowed ports

...
sudo ufw status
8090                       ALLOW       Anywhere
8090/tcp                   ALLOW       Anywhere
8090/tcp (v6)              ALLOW       Anywhere (v6)
...

Nginx conf:

server {
        listen 8090;
        listen [::]:8090;

       root /var/www/data.poutnicesty.cz/;

        index index.html index.htm index.nginx-debian.html;

        server_name 89.221.222.178:8090;

        gzip            on;
        gzip_types      text/plain application/xml text/css application/javascript;
        gzip_min_length 1000;

        access_log  /var/log/nginx/data.poutnicesty.cz.access.log;
        error_log  /var/log/nginx/data.poutnicesty.cz.error.log;

        port_in_redirect off;
        proxy_set_header Host $host:$server_port;

location / {
        proxy_pass http://127.0.0.1:1337;
        proxy_http_version 1.1;
        proxy_set_header X-Forwarded-Host $host;
        proxy_set_header X-Forwarded-Server $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header Host $http_host;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "Upgrade";
        proxy_pass_request_headers on;
    }
}

I thought it is enough just allow port (for other "subdomain" it worked, ex: port :8050 - but there I tested that with nuxt app, not strapi).

Any idea?

Thanks a lot.