I own a Kagi family, and one of my family members has created and shared a lens with me a while ago.
When first shared, I enabled it and added a quick bang for it.
Today however I wanted to disable the lens, and realised that it does not allow me to do so. It will look like it's disabled, but a refresh of the page will simply put it back to enabled.
I had a look in the dev tools network log, and I see that the API returns a 403 for the POST call to subscribe when I try to disable the lens.

The form data for the POST request to subscribe is simple, lens_id: "18251". Its response equally simple:
"You cannot subscribe to this lens!"
I am also not allowed to view the settings of the lens, this returns an empty screen (but no 403 in the log).
I expect to be able to disable the lens, and also to at least be able to view its settings.