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So, when you throw a ball and you miss, the ball rolls around. You can click on it to get it back and not waste 20 balls on a Pidgey. Well, this works sometimes, and the ball is just laying there, behind the pokemon, but most of the time, the ball disappears almost immediately without me clicking on the screen or anything and its not back in my inventory ? SO what's going on, am I retrieving my balls wrongly or are they disappearing by design ?