You can block the user which you do not want to display chat to.
(1)After logging into ChatPlus's management screen, click [Visitor] at the top of the screen.
(2)The list of visitor will be shown, so click the user that you do not want to show the chat to.
(3)Click [Edit] at the top right of the screen.
(4)Check in the box "Do not display chat" and click [Update].
(5)Check to see if the block mark is displayed.
when user is not blocked
When user is blocked