Install behind a router

Hi guys,
i’m new to jitsi.

I’ve follow the installation guide:

and inside my home network all works fine.

But if someone try to access from outside, they try to connect for few seconds until connection will be lost.

I’ve also follow the advanced chapter but with no lucky.

Any suggestion?
Little more info:
I’m using ubuntu 20.04 on vbox with a bridge, on my router i’ve opened 80,443,4443 ans 10000 ports