Every booking confirmation includes a link the attendee can use to manage their own meeting. They don't need a SalesCal account.
The link opens a Manage Your Meeting page showing the meeting details, with two actions:
Reschedule Meeting — pick a different slot from your live availability
Cancel Meeting — cancel, with an optional reason
The link is unique to that meeting and works without signing in.
The attendee sees your current availability, exactly as it stands at that moment, and picks a new slot. Your calendar is updated, the old slot is released, and both of you get a confirmation for the new time.
Because it reads live availability, an attendee can only move to a slot you're genuinely free for. They can't reschedule into a time you're busy.
The attendee confirms, optionally gives a reason, and the meeting is cancelled. The slot is released back into your availability, and the meeting is marked cancelled in your dashboard.
If they give a reason, you'll see it against the cancelled meeting. That's worth reading periodically. A pattern in cancellation reasons usually says something about the offer or who you're attracting.
The alternative to self-service is an email asking you to move a call, which you then do by hand. The link means the reschedule happens without you, and the slot gets released for someone else rather than sitting dead in your calendar.
If an attendee reports the link not working, they'll have seen:
This link is invalid or the meeting has already been cancelled.
The usual causes:
The meeting was already cancelled, by them or by you
The link was truncated, which happens when it's copied out of an email client that wraps long URLs
They're using a link from an older email for a meeting that has since been rescheduled
Ask them to use the link from the most recent confirmation email. If none works, cancel or reschedule from your Meetings page and a fresh confirmation goes out.
You can cancel or reschedule any meeting yourself from the Meetings page. The attendee is notified either way, so there's no need to email them separately.
The cancel and reschedule links are part of the booking emails. If you'd rather attendees came to you instead, that's controlled by the event's notification settings, where you can choose whether reminder emails include the cancel and reschedule options.
Think carefully before removing them. Attendees who can't reschedule tend to no-show rather than rebook.