Talk high performance backend clients connection problem

I finally setup HPB standalone, and I can connect to it from my nextcloud instance, but I have a problem; When I try to make a call, each client (via browser) could enter in the conversation/room, make the call, but it’s impossible to establish the communication.

The error is similar to this post:

My configuration is behind ngnix proxy manager, and I suspect that could be the problem. = my DMZ = my LAN = NGiNX proxy manager = HPB server = Client

systemctl status signaling

client.go:303: Error reading from read tcp> use of closed network connection

Someone has configured it behind a reverse proxy or on a DMZ? What could be the problem? I have to open/NAT some UDP/TCP ports different that related to TURN server?

Currently I NAT 80/443 ports from internet to my Reverse proxy on the DMZ, and the TURN port 5349 to my HPB server (On my DMZ as well)
My Reverse proxy take all the traffic destined to my HPB server and point it on 8080 port.

This is my NGNIX HPB configuration:

I am so near to the solution, but I can’t understand where the issue is.