It is rare that a client would be deleted. However, it may be that a duplicate client was inserted by mistake, or a client has requested that their information be removed forever.
To delete a client, click on 'Clients', and then on 'View Clients':
Search for the client you would like to delete:
As more than one result may appear, click on the client you would like to delete, scroll to the bottom of the page, and click on 'Delete':