To add Unavailability,

1. Go to Schedule and click the Add Unavailability button.
   
2. An Add Unavailability window will pop up. Fill out all of the necessary information such as Start Date, Start and End Time.
3. If the schedule has to be repeated, click the Repeat button.
4. Choose the days when the unavailability should be repeated, and set the End Date.
5. Once done, click Create.
   

Once saved, your schedule should reflect your unavailability.