Secure a line, or maybe line isolation?

[Factory909]

We have an old Partner system in one of our buildings. Two line setup. If user is on line 1 using the phone, user 2 can push line 1 on the phone and listen in. Is there a way to isolate the lines so users can't listen in?

 

[budbyrd]

Privacy. In programming it is #304 and assigned by ext.

Dermis and feline can be divorced by manifold methods.*
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