If you purchased items on the store and did not receive them, here's some tips you can try: 
 

1. Make sure that you open all of your token and item boxes. These are the boxes that spawns in front of you when you first load up the game, or you load into an area like the ^RecCenter. Most of the time, the item that you are unable to find will be in your box queue. 
2. If it's an avatar item, make sure that the item is not in your wardrobe already. Take a look through your avatar items when you have a chance in your ^DormRoom. 

If you're still unable to find your purchased item after trying these steps, please submit a support ticket.