We have a small CS department that has two agents. When neither of the two are signed in (usually it is one calls in sick and the other one goes to lunch) and the receptionist tries to forward a call into the queue, the call gets a busy signal. Outside calls that go directly through the 800 number go into queue fine and after a certain period of time they are asked to leave a message. What might be going on that a call being forwarded into the same queue is going busy?