If you recently joined a working group or project group, that group may have existing, recurring meetings. 

By default, Workspace will only show the next meetings in the event tab.  Adding that meeting will only add that single meeting event to your personal calendar application.  It won't add the complete sequence.

If you want to have the complete, recurring schedule in your personal calendar application, then it's important that you add the FIRST event in the series.


Identify the meeting series you want to add.  Click on the icon next to the meeting name.   It's important that you only click the icon, not the name of the event.

If you clicked on the icon, you will get a similar pop up that shows all events, past and future.  
Here, you need to click on the first one in the series.  Click on the name of the event.

Now that you have clicked on this, you will get the event details of the first event.  Double check the date here matched the date from the prior windows.

When you click "Download to your calendar", you will get the entire sequence.