Someone who should not have it has my feed URL
What you are seeing
Someone who should not have it has my feed URL.
#Why it happens
A feed URL is a bearer credential. Anyone holding the link can read that calendar's events without signing in.
#What to do
Revoke the link (Subscribe → Revoke link, or an admin's Revoke all), then create a new one. Never paste a feed URL into a shared page or ticket.

#Related
Turned off the "Calendar subscriptions" feature but existing links still work
The toggle only blocks creating new links; it does not revoke ones already handed out.
"Dates" column and the Calendar panel badge in Capable Search show fewer dates than the page has
Those two read the page without the app identifiers needed to recognise Capable Event macr
Everything else
The rest of this family.
Found it? Good.
