I'm having a problem with a phantom device linkined to a voice mailbox. I have everything set up so that this device acts like a normal extension on DND so that we can use it to dump annoying sales calls into voicemail directly by either transfering an incomming call to the line manually or by giving out the extension to callers that we deem to be annoyance calls. I'm able to leave messages internally and externally but nothing ever shows up under the mailbox, i.e. it always shows no new messages. What am I missing??