1. To edit a meeting appointment, you have to be first on your operator account.
2. Press on the Meeting appointments tab from the menu.
3. Then press on the List tab from below in order to see all meeting appointments in calendar view.
4. Then press on the Search button above the calendar.
5. Then press on the Edit button ( ) from the Actions column of a meeting appointment.
6. Here you can modify the wanted fields. After modifying the fields, press on the Update button in order for the changes to take effect.