Item ghosting with NBT timer

I'm making this procedure where every 10 seconds, the player obtains an item. The issue is every once in a while, the player will gain an unusable ghost item that doesn't do anything. It's not game breaking but, its a little frustrating. It says something about NBT entity get is not synced between client and server. I assume that's the issue i am facing but am unsure how to resolve it. Thanks for reading.