Ok so I moved into a new house and the house is bigger then my previous one which meant my a7 router wasn't enough to cover the whole house so what I did was drill a hole to the room below where my pc room was I drop a Ethernet cable down the hole and connect another router Wi-Fi working great and the speed is what it should be my problem is when I connect my Xbox which is downstairs with the 2nd router it tell me I have double nat which I heard is bad for playing online how can I fix this? My set up is my Xbox one connect thru Wi-Fi to a router optimum gave me that router is connect thru a Ethernet cable that go up to my a7 my a7 is connect to a modem that optimum gave me so my set up is modem >>> a7>>>optimum router >>> Xbox one 

ps my optimum router is far from my Xbox so a direct connection is not possible which is why I'm using Wi-Fi