The two main causes are either:
The END DATE has passed. So the event will no longer appear on a member’s list of events view. You can edit this by:
Select Calendar under NEWS & CALENDAR in the left bar. It will bring you to this screen:
Select ‘Update New Event’
You can then change the date of the event.
OR
The event is inactive.
You can make the event active by selecting the on/off toggle at the top right of the page under Configurations.