Port forwarding / Devices not showing

I see I am not alone in having devices not showing through my Xfi and am thus unable to port forward key devices in my household. In the topics there are several identical issues discussed that say "answered" but the "answer" remains inaccessible to me as your website just kicks me right back to the content page.

What can I do to make more than just 6 generic devices show up on my Xfi advanced device settings? I have rebooted, hard/soft a thousand times. These are also devices that have literally been connected to this house's internet in some form or another since BEFORE I made this terrible switch to Xfinity. The particular device I'm trying to access is literally my MAIN computer that's been with me for years and years now for what it's worth.

Thank you,

Happy quarantine