Remove one event programatically from calendar

Is the one date of an event, or one event. If the former then you probably want to call eo_update_event() and included the date in the ‘exclude’ argument. See codex: https://codex.wp-event-organiser.com/function-eo_update_event.html. Alternatively you could use _eventorganiser_remove_occurrence() – but this is a private function. That is, in future updates it may be changed or removed without warning.

If you want to delete the entire event, you can use wp_delete_post().