This article explains how to create a time block using the mobile app.
Time Blocks can be added to your calendar if you do not want clients to be able to schedule with you at specific times. It is important to note that time blocks override your regular work schedule.
On the Calendar screen, tap and hold on the desired time slot on the calendar. Alternatively, you can also tap on the "+" icon on the top right corner.
Select Create Time Block.
Select the duration. Add additional notes, if desired.
Tap on Create button to save.