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I have a bug on my store already existing. How it works is my store is integrated with a IPB database. The store is ran off tokens, you purchase tokens then can purchase items in the store. Once the items are purchased in the store it sends it to a store_collection_box table to be used by another application off the website. The bug I am having a problem with is that when 2 people hit the buy button at the same time on the same exact forum account it executes all the querys & page at the same time allowing people to purchase 2 items for the price of 1.