My animations won't work, however the drooling zombie animation (default) works?

I am making a sword animation, however it won't play. I'm doing this for a mob, so i tried the drooling zombie as a configuration adds the animation in. The drooling zombie default attack animation plays (the animation it comes with i mean) , however any of my animations, which i made in the last hour or so refuse to work. Is there a reason?