Xbox nat is strict. how do i open it using the tmobile gateway?

I took back the T-Mobile Home Internet and got the Verizon Home Internet. It has all the needed interface to open ports and DMZ. It works. Its $35/mo with an unlimited Verizon line attached, $60 otherwise. T-Mobile was $25/mo with their Magenta line attached, $50 otherwise. Total bill T-Mobile would be $108 for both services, Verizon $130. You do get Paramount+ with T-Mobile, you get Disney/Hulu/ESPN+ with Verizon. Main thing is that you can online game with Verizon, T-Mobile requires work arounds/VPNs.