While using the Switchboard, you can enter edit mode to lock or unlock a contact.
First, use the search bar to find the contact you would like to lock or unlock. Then click the Edit icon on the left of the contact's name. The actions on the right will change to show either Lock or Unlock. Clicking Lock will result in displaying 'Stop' every time an agent views the contact. An agent must read the note before proceeding.
To lock a contact a note must be added.
Clicking Unlock removes the 'Stop' but the note remains in place. If you clear the note field the contact will be unlocked. To re-apply the lock you must enter a new note.
Click the Edit icon again to leave edit mode.
More on the Switchboard