Hi Andrman,
Is the meeting being canceled from a different device, and just not syncing to the Mac?
Instead of deleting the calendar and adding it back, do you not see the option for delete? This is found in the main Calendar User Guide, Add, modify, or delete events in Calendar on Mac.
Delete an event
In the Calendar app
on your Mac, do one of the following:
• Select the event, then press the Delete key.
•. If you receive a calendar event from an unknown sender, you can report it as junk and delete it without notifying the sender. Double-click the event, click Report Junk, then click Delete and Report Junk.
Reach back out if you still need help, and let us know more about what device is being used when canceling, and the steps taken.
Take care!