I have an OBI202. I originally programmed it with a single GV number for both line 1 and line 2. I am trying to change line 2 to a different GV phone number and keep Line 1 on the original one I signed up with. I've tried changing it in settings, but still have only the one number ringing through to both Lines. What would be the easiest way to get this set up the way I want it?