Problem: You are not getting any calls, but you are getting new voice mail messages. In addition people have reported to you that they have called you, but got your voice mail.
Cause: The most frequent cause is that your has DND (Do Not Disturb) enabled.
Solution: Check the display on your phone. If either "Do Not Disturb" or [DND] is shown on the display the feature is enabled. To disable it on a Polycom phone there will either be a physical button labeled "Do Not Disturb" or there will be a softkey below the display. Press the button and the display should update. On the Yealink phone you should see the [DND] displayed in the upper right hand corner of the screen. To disable it toggle the DND softkey below the display.