How to limit one extension one call?

[cd123]

Sometimes an extension makes more than one call at the same time. I want to restrict only one call can be made at the same time. How can I do?

 

[lneblett]

This is more likely accomplished at the phone rather than the PBX, but the limitation will be for both internal and external calling.

The phone would need to be registered as a single extension/account and all other line keys or other buttons your phone make/model may call them by will have to be programmed to something else so as to preclude the user's ability of being able to make get another line.

Given the wording "make", as in meaning to initiate a call, is how I answered, but this will also likely affect "take" as in only being able to receive one call as well.

Keep in mind that this will impact that extension's ability of being able to put one call on hold and then needing to make another call for any other reason.