How do I close an Open Enrollment Opportunity?

An Open Enrollment Opportunity, is  by nature, "Ongoing". There is not a setting to close registration (like there is with a Fixed Date Opportunity). What we recommend is changing the Privacy Setting when you would like to "close" the Opportunity. 

Changing the Privacy setting to "Private" will ensure that users searching for Upcoming Opportunities will not see this Opportunity. All users who have already been approved will continue to have access to it. It is also possible to share the link with a participant who needs to apply after it has been set to "Private".