Brought in? Are you saying you removed the previous ATA and installed a new one? If the previous one was working, why did you replace it? Or are you trying to add more lines? You have to program the new lines into an outbound hunt group, and then direct incoming calls on them to a destination elsewhere in programming.
It would 'seem' that you got the first part done.

When I was young, I was Liberal. As I aged and wised up, I became Conservative. Now that I'm old, I have settled on Curmudgeon.