Don't use the drop button, use the "release" button.
As a note, the agent id form and the station form don't actually have to be the same.
In the agent ID form, you have the following options for auto answer:
none: No auto answer. This will override any "auto answer" option you have on the station when the agent is logged in.
station: The will follow whatever entry you have in the station's auto-answer field.
acd: This will activate auto-answer. It will override any "auto answer" option that is on the station form.