If you wish to deactivate a chat room, select the three dot menu to access Chat details (Figure 1):
Figure 1 Chat details
Scroll down past the Permissions section and select Deactivate room (Figure 2):
Figure 2 Deactivate room
Confirm you want to deactivate the room, at which point the room will be removed for all room members.
Note: You can only deactivate chat rooms that you are an owner of.
Note: You cannot deactivate direct chats.
Note: Refer to the Knowledge Article found here for further information on reactivating a chat room.