Multiple call answering?

[subnetworx]

We have phones which have multi line appearances. Aastra 9133i and 480i's. The problem I am having is when another call comes in; a person on the phone can not put the call on hold, and pick up the new call.

I think I know what the problem is, but I want to have someone clarify this.

Each line appearance has the same settings for the individual users. e.g. User 3300 Line one 3300 Line 2, etc.

I did this so when a user calls another extension, the receiving extension would not be confused.

Is there a way that is probably obvious that I do not understand?

Thanks in advance!