I just install a M12X0 expansion with 2 trunk cards. I have it all wired into the 8x24, and the KSU SEES the 8 lines. How do i use the lines though? I tried activating lines 9-12 but they say "not in service" when i try to use them. I have the M12X0 plugged into port 3 of the expansion on the KSU. How can i use my new lines?