Your model name is not a valid Java name

I am very frustrated. I finally find a way to make custom mob models, and now I can't even use them. I am using an application called blockbench. Whenever I try to import my model, it says the name isn't valid. I have changed the name multiple times, to fit the requirements, and I don't understand why it is still wrong. there is no numbers at the beginning off the name, no whitespace, and all the letters are valid ASCII! the name is literally np.java!