[Do not display the chat for a while] can be set when the chat ends.
By default "For a while" means a day. (2019/11)
You can change the settings below.
(1) Click the setting button on the upper right of the management page.
(2) Click [Chat]>[Design]>[Menu] on the left side of the screen.
(3) Click [End] tab.
(4) Click [Display detailed settings].
(5) Enter a number in the section [Hide the chat for x minutes] in [ Do not display the chat for a while].
(6) Click [Update].