I also had the same problem, I used charcoal in the box Solid charcoal closed the box, no luck. kitty litter for a week, no luck. fabric sheets, no luck. you name it, I tried it, with no luck. I no longer have the box!!! I hope you find how to solve the problem, I love the machine its great for when you take a class, light weight to carry, I bought a canvas bag works well!!! A very dear friend had a feather weight she bought brand new for $59.00 when they first came out smells wonderful.