I recently purchased this trap & began using it immediately, since I have had an infestation. It took a while to finally catch a mouse or two (a few times) but then all of a sudden, the bait was chewed up and no mouse inside. How on earth did they get out is what I would like to know? Does this mean that my trap is no longer working? I clean it after each use, since the mouse dung reeks and I am allergic to it if I touch it. This is now my second have a heart that has failed. I am giving it one more go ahead tonight. They love popcorn with nutritional yeast on it! I am considering buying another type. Any recommendations?