Itunes machine authorization?

Ok so I had music on my other computer and I deauthorized that computer (itunes) and then put it on my laptop because I use that more, and I just got an Iphone so I wanted to transfer all of my old music to there. I authorize it and it says "Machine Authorization Succesful" And something about I have 2 out of 5 machines authorized, but it won't let me play the song!!!!!!!!!! Can you help me please!