We have an NEC SV8100 at a small school. Currently we have 3 lines coming in from Verizon. We would like to set up our system so that when a call comes in our main number, while that line is in use, if another call comes in, our system would automatically roll over to our next line. At present, the system is set up so that once line 1 is in use, when a second call comes in, they get a busy. I can log into the admin area and have full access, however, I have no idea where this feature is located. Many thanks!!!