This is forums support, not tf2items support, best to post further questions here http://forums.sourceop.com/forums/28-TF2items

As for the error, its not an error, just means their is no item history for the particular item currently. The site only updates when an inventory is viewed and histories are further prioritized by how often a profile is viewed and some specific items (buds/unusuals) for example. Hope that answered your question for you.