Game Natstrict on advanced warfare xbox one

[#1]

HI, my xbox shows my settings as Nat open but when i go into advanced warfare it states nat strict? this is stopping my son from being able to join his friends :(. I have tried the port change recommendation on the help and support page but its done nothing. I have a Technicolor router. Any help would be greatly appreciated. i am a numb female that knows NOTHING about technology and all the ports and nats has drove me mad and ive got nowhere. Thanks for any help at all.

[#2]

on router find your xbox and tick always use same ip.then put that ip in dmz.on xbox use auto settings 

[#3]

Hi there, I have 2 Xbox One's in the house & both are getting this problem with the Strict NAT on the game but on the xbox network settings it says open. The DMZ only works with one Xbox. I am looking to get both of the NATs open so that they can connect with friends on the game etc. I have struggled with port forwarding & it simply has not worked is there any other way i've seen someone post about disabling the firewall can work but i'm out of ideas any help would be greatly appreciated so I can get these 2 nat types open. Thanks

[#4]

if you have open nat on dashboard then you need to find what udp ports the game uses then use telnet to cone the ports then only use upnp

[#5]

I honestly have no idea even how to get to that  any chance you can post a link how to help me do it?