Hello i want to deploy a Ubuntu Server with rustdesk!

I ran the script which was given by https://rustdesk.com/docs/en/self-host/install/ and it works in our LAN but not from outside.

I made a NAT with our the public IP to the intern IP.

I opened the ports:

tcp 21115-21119; 80; 8000 and 443

udp: 21116-21119

and made a subdomain which is directing to the right IP.

I tested it already with my phone and i am able to connect to the apache webserver but not with the RustDesk Server in my client.

We have a Watchguard Firewall and i am not seeing anything blocked by the Firewall, at least with the IP's i am trying to connect with the RustDesk Client.

Can you help me?

Is there anything on my Ubuntu Server that could block the connection from outside or do i miss to install since i only installed by the given script?