Superfast Upload Speed Is not as Described

Hi, I am new to Xfinity. When I purchase this plan it says 800/100. The download speed is great, however, I am only getting around 20-24 for the upload speed sometime around 10 on mobile. I am working from home and causes me issues. I am using Arris G36 DOCSIS3.1 which is Xfinity recommended devices. Is there any way I can get 100 upload?