Thought you said that when you plugged an 18 button into those extensions the three lines were there? Are you saying that if you take the 6 button to another extension they work?

When you plug the 18 button into the 6 button extension, do all three lines appear in order, bottom row from left to right?

Do this- go into system programming, #301 and then a 6 button extension. Press "remove" then reassign(1)- L01, 02 and 03. See if that works.

-Hal

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