model 1070

ok when you have the 4 lines. Say line one rings. you put it on hold and another phone picks it up. On the original phone it still flashes green and beeps and you are able to listen in to the call. when the person on the second phone hangs up the original phone still beeps like the call is still there. I got a new set of these phones so the old set had everything set up right. I am going crazy. Does anyone understand what I am talking about? I need HELP!!!!