Need help/info disabling public Xfinity hotspots on my modem.

While provisioning my modem, I asked a phone live agent to also disable the public hotspots on my XB10 modem. She said she could not do it, but I could do it on my Xfinity App [which is not working*]. (The wifi was left as the default for me to change later as initially I did not intend to use XB10's wifi capability, but rather to use the wifi on my router for greater control and anyway I intended to put it into bridge mode which disables wifi.)

* The problem is my Xfinity App is not working on either a Pixel 8 or a Pixel 9. The app says I am signed in, but while I can get ads it says my home internet is offline which is incorrect (regardless of whether I am in bridge mode or not. It is working well for both ethernet and wifi including the router's wifi SSIDs and the public Xfinity wifi SSIDs and the special Xfinity hidden network. I cannot get to any option to control my wifi password. Logging into the modem at 10.0.0.1 let's me see its wifi SSID and the current password, but not to change it, nor to disable the public wifi SSIDs.

I want to disable the public hotspots for security reasons as while it is said they are walled off from my system, hackers are clever and I want to mitigate any possibilities.

Is it correct the phone or chat agents cannot disable the public wifi hotspots?