Caller ID shows the server's ip

I have searched and searched and can’t seem to find an answer so I thought I would post it here.

We have a T1 that comes into a Cisco 2811 router that then sends most of the lines into a Call Manager Server, and those phones have caller id. We had a couple of lines not being used so we got in the router and set up some sip and directed them to the freepbx server. We can make calls in and out just fine, but when I call in from the outside my phones say the call is from 1921682200 and gives the freepbx IP.

Everything I have found talk about the zapata.conf but I don’t have one of those. I’m still in the process of learning freepbx so go easy on me.

Any suggestions??