Deleted calendar events keep reappearing (solution)

This kept happening to me: I’d delete a calendar event, and a few seconds later, it’s back.

I read the possible solutions - including signing out of icloud and signing back in - but none of those stuck.

Because for me my master calendar was google, not icloud. To keep the offending events from reappearing I had to delete them in the google calendar app.

I hope this helps others