Most modern building, office, or car windows are equipped with UV-blocking glass or window tinting, which can block over 90% of the ultraviolet rays needed for color-changing erasers to react. To get a proper test, please try moving it outdoors into direct, unobstructed sunlight or opening the window completely. It isn't supposed to be put in the freezer because it may damage its structure and the color changing material.
Could you give that a try? If it still doesn't change color, just let us know and we'll be happy to provide further assistance!
with ♡ + respect
Isabella Lee
A Lot Mall | Customer Happiness
