NAT type

How can I know what kind of NAT I’m at?
I guess that the red and green bright gems in the characters profiles when you hit TAB are an indicator of the NAT type.
However, my IP is set as DMZ in my router and I have a fiber connection that gives me no trouble at all (22 ms ping in Overwatch, for example) Any way to fix this issue?

Why not join the Fatshark Discord