Some confusion with Listen in ability

[MikeSNC]

Hello all, relative newby to admining 3cx. I gave a user the Barge in Right in 3cx. She is reporting that it somehow only works sometimes.
The user she is trying to listen in will have brackets around the number they are talking to. If the brackets are there, my user can listen in. if not, she cannot.
The brackets are only there sometimes.
I am looking for clues as to why the listen in ability isn't always on (available) to this user.
Let me know any thoughts or further info I can provide.
thanks everyone!

 

[Saqqara]

It is always the same extension, the person can not listen into ?

Are the extensions in the same 3cx group ?

Which application are you using - windows , or web client ?

 

[MikeSNC]

yes, there is on main person she is trying to listen to. we still just have the one group "default" so all users are in this group. web client for 3cx.