I went through this same kind of problem and researched and got all sorts of advice.
Are you sure you are doing the cage correctly? You have to put it in a place the cats will travel, have the proper size, give the proper bait, and be patient. Also, what are you going to do with the cat once you catch it? I assume you did what I did and got the cage from the local shelter and would send the cat there. Make sure your neighbors don't see you catching or transporting the cat. Cat owners who allow their cats to illegally go off their property generally don't like anything anti-cat and won't do anything even if you, say, put notes in their mailboxes.
My cage didn't catch all the cats. Mothball and other deterrents didn't work. I finally found my last resort worked: a BB gun. Just don't be too close to the cat, as actually injuring one could be illegal.