Inbound calls to an extension route directly to voicemail (Do Not Disturb rule), even though the user is in Available status and the desk phone is not in DND
Virtual Office, Virtual Office Desktop
In Virtual Office Desktop, set the extension to Do Not Disturb then back to Available.
Sometimes the status shows as Available when the user is still in DND in the back end. Toggling to DND and then back to Available updates the setting in the back end.