Disable xfinitywifi and XFINITY wifi networks

I am unable to disable the "xfinitywifi" and "XFINITY" networks on my router/modem. Things I have tried:

1. Through router administration: I've tried disabling the private 2.4 GHZ and 5 GHZ networks as I don't need them. Even after doing so, the 5G light continues blinking on the modem itself (2.4GHZ stops being lit). When I do a wifi scan, I still see "xfinitywifi" and "XFINITY" networks available with a similar MAC address.
2. Through the business account dashboard at https://business.comcast.com/connectivity/internetdashboard/. When following the directions at https://business.comcast.com/help-and-support/internet/troubleshoot-xfinity-wifi?linkId=134940491, the dashboard shows the private 2.4 GHZ and 5 GHZ networks, as well as the "xfinitywifi" network, but the cog next to "xfinitywifi" is a circled ! instead, with a tooltip saying the "modem is offline". That's not the case, since the dashboard is properly showing the private networks. This also doesn't list the "XFINITY" network, which I also wish to disable.

Next steps?