Calls transfer while busy on a call

Hi all,

I have a strange problem, while busy on calls, our calls are transferred automatically to a different person in the branch, so it just looks like a new incoming call.
We are using Yealink T21P E2 and Atcom phones, although I doubt it is anything on the phone itself.

Did you check config on the phone. It sounds like on yealink you had set call forward.

Yes i checked the config and it is not set to forward. We (IT) do the setup of the phone, they do not have access to the settings to set forwarding.

You’ll need to provide the Asterisk console output during a call where this happens to see if there’s anything that explains it on the Asterisk side.