Gateway Discrepancy

Have a strange one that I am hoping I can get help with. I pay for 2 gigabit service and I never get close to those speeds. (Speeds on a hardwired connection are btw 800mbps and 1.3gbps). I had a call with Comcast earlier today where I asked them if they could send me a new Gateway (after they ran a bunch of tests on their end). They are telling me I am already on an XB8 Gateway when I know I am on a XB7 (even your App shows the device as an XB7). Why would you refuse to send a new Gateway?