If you notice water spraying in a straight line rather than a fan of mist, the nozzle may be partially clogged.
To fix this, take a fine sewing needle and poke it in and out of the nozzle. (You can try this while it's misting).
You can also remove the nozzle and soak it in vinegar and baking soda. To access and remove the nozzle, check out this article.