As an administrator, you can turn on do not disturb feature on behalf of an user. When enabled, callers hear the busy treatment. You can also enable a ring reminder which plays a brief tone on the user's desk phone when they receive an incoming call while on do not disturb.
Sign in to Control Hub, then under Management, click Users.
Select a user and click the Calling tab.
Go to the User call experience section and select Do Not Disturb.
Toggle on Do Not Disturb.
Select the Enable ring reminder on your Cisco IP phone check box to notify the user when a call comes in.
What to do next
If you'd like to set up calls to go directly to voicemail, when Do Not Disturb is enabled, you must enable the When busy treatment in the Voicemail Settings. For more information, see Configure and manage voicemail settings.