Customer has 4 bcm's. 3 50R5's and 1 450R1. They are networked together and they 3 digit dial between. I am having an issue with 1 station at one of the sites. They forward their phone to their cell phone, and when they do that, theres a "extension not in service" error when 3 digit dialing. Everyone else who forwards to a cell, no problems. When forwarding is turned off, the 3 digit dialing to that extension works perfectly. Any ideas why that 1 extension would have the issue?