All in a sudden one of my co-worker's phone is not working. When someone call it from the outside line. Once dial the extension. It saids "please wait while we transfer your call". Then it goes "transfer failed". Looking at the main control panel screen and it looks normal, all green lights. I don't see any problem. Does anyone how to fix it ? Is there a service I need to restart ? I have rebooted the phone couple times but still not working properly. Other phones in the company can transfer calls fine.