The /dnd command is used to set Do Not Disturb which prevents any users from being able to whisper you. You can enter text after the /dnd which will be shown to any one attempting to whisper you.
Example: /dnd playing a game would show "Playing a game" to anyone attempting to whisper you. Ensure you do not put any sensitive information after the /dnd as any one attempting to whisper you will see it.
