I have a site that needs to be able to know what line is ringing so they can answer with the correct Company name. For example someone dials 222-3333 which is lines 1 & 2, and they answer with ABC Company and then some dials 333-6666 which are lines 3 & 4 and they answer with Customer Service, etc.. I have given the lines their own ID but nothing comes up when I dial these lines just the usual CID info. time and date on the display of the 2420 digital set. What is the best way to set this up please. Thank you