NAT MODERATE

Hello, I have just installed this mini router in order to use a VPN on my PlayStation 5 console. My problem is that my nat type remains moderate on the call of duty game and my speed is extremely reduced. I have an Orange box. How to open ports efficiently?
I assigned a fixed IP to my console.

Thanks in advance

VPN will mostly never bring a better NAT.

Try without.

Even by removing the VPN I have this problem

NAT moderate means you are not connected direct to the Internet, there is a NAT in between. That is how a router works.

A solution could be to find out which ports the PS5 is using and forward this ports from WAN to the PS5.

I know the ports used but how do I transfer them?

Here you go: Port Forwarding - GL.iNet Router Docs 4