I have a digital phone on this system that I am trying to call forward off premise. It has a DID number assigned to the extension in the translation tables. I goto the phone and activate the call forward to a cell phone, 9+ area code and number. It accepts the forwarding and my feature key flashes. I than call the DID number and the phone on the desk, does not ring and does not show any signs of an incoming call. I hear ringing in the phone I am using to dial the number but it does not ring the cell phone I forwarded to. I cannot tell where the call is going. I have cos set for off premise and trk to trk transfr allowed. I have the phone in the right COS. not sure what else I can do or if maybe it is the carriers PRI???