It was a call from someone collecting for The College Network

I got a call at work from this # asking for ext ***. I said may I ask who's calling & he said sure..................................& stopped there. I said excuse me & he said you can ask but I don't have to disclose. I said I don't have to transfer the call if you won't disclose it & he hung up on me. I looked up the # on Yellow Book & it was The College Network. I called back & told them to remove my #. We'll see what happens.