Why isn't my Space sleep bag glowing?

As shown in the product description, the Glow-In-The-Dark fabric on the Space print needs to "charge". We suggest that you charge the sleep bag indoors under a bright light for at least 30 minutes before wearing. Indoor lighting is more effective than sunlight. The sleep bag will start to glow as soon as it is removed from the light and will then last for about 3-4 hours. For maximum glow, you want to charge the sleep bag just prior to wearing.