Anybody can advise what is done wrong in my set up?

I'm trying to set up Startalk mini in our office. I compeleted all programming set up AA to pick up after 2 rings, but VM doen't do so.

I did try with 2 systems (3x8 DR5 DS & 8x24DS DR5) and still have the same problem.

I connected VM to one of phone extentions on BIX.

What I'm doing wrong? Any help is greatly appreciated.