In the mandatory fields, you can specify which fields must be filled in during appointment entry in order to save an appointment. If you do not activate these fields, you can also save appointments with "empty" data, which may result in inconsistent customer data.

Gender Default
If the majority of your customers are either female or male, it makes sense to set a default here so that gender only needs to be explicitly selected if a customer belongs to a gender not specified here. This is suitable, for example, for nail studios or barbershops.
If you do not set a default here, employees must click on the gender each time to ensure clean data.
Mandatory Fields
Specify here whether name, phone number, and email address must be entered during appointment entry in the calendar, or can be left blank if needed.
For example, if you set the email address as a mandatory field, an appointment cannot be saved without an email address.