First off, we strongly advise you not to delete clients. Instead of removing a client we recommend that you just unauthorize their card. This is in case the situation changes in the future and the client wants to again do business with you. If you would want to do business with them again, too, all you'd have to do is authorize them again, rather than have them sign up again with a new email address and rebuild the whole history of which candidates they liked, which ones they didn’t, etc.
Furthermore, removing a client from the platform usually just pushes the client to sign up with a different email if they try to return.
That being said, if you do wish to remove a client you do so following these steps:
Clients Tab>View Client>Scroll to the bottom of the profile and enter the word “delete” in the text box. Then Click the Delete button on the right.