Double NAT

Hey there,

I've been having an issue with Double NAT for the last few days now and I haven't been able to solve it. I'll do my best to explain the situation:

I have a Asus RT-AC68U and a Huawei B612 LTE CPE Wireless Gateway. They are connected to each other via their respective WAN ports. The gateway's IP is 192.168.1.1 and the Asus is 192.168.2.1

I have set the Huawei in bridge mode so that the Asus does all the heavy lifting. However, I'm still getting a Double NAT warning on my Xbox...

Double NAT