Here's a VIDEO that may help you- Service and sub service types not visible while creating appointments or you can also use the following instructions to solve the issue.
1. Go to "Employee" located on the left menu and then tap on the filter icon next to "First Name."
3. Search your employee's name and click on the employee's first name once the results have come.
4. Scroll down and tap on pencil icon below the "Service Type/Service Subtype Exclusion" section.
5. Once the menu appears, tap on the arrow facing to the left box for both arrow sets, then save both empty boxes to the right.
6. Now go to "Appointments" located on the left menu.
7. Click "Add Appointment" on the top right of the calendar and then select your "client", "service type", and "Schedule Start Date" once the menu appears.
9. Then save and you're done
Final Product:
