If your calendar seems a bit out of date, you can trigger a refresh by pressing the manual re-sync button at the bottom of the meeting section. Note that when you are in the 'My Week view ' the re-sync button displays there instead of in the meetings view.
This should help with meetings that have recently been added to your calendar, or meetings that have removed or rescheduled.
You can also tell when you calendar was last synced, by hovering over the button.