You need to add the receptionist (or any user you want to give access to your calendar) to the appropriate group. Follow the steps below:
Click Settings > Users.
In the relevant group, click Add User.
Enter the user's name, select their role type and access level, and enter the required information. Tick the Calendar checkbox to ensure they have Calendar access.
Click Save to create their linked account and add them to your account.
Click Personal > Locations.
In the Hours, Profile and Booking Preferences section of your new location, click Add practitioner.
Select the new user from the drop-down menu and Save.