I've had my Instax for about a week and I've only used it once. It worked perfectly fine when I first tried it, but now (again, I haven't turned it on for a week) it starts ejecting all my film out nonstop, without me pressing a single button (all the pictures end up completely black). It won't stop and it still goes for awhile, even after it's been shut off. What's going on and how do I fix this?!