I'm making a classic card game by Unity. I created a first deck and when I click on the top card it is discarded and it moves to another second card stack. When the first card stack is empty then it is refilled when it is clicked. Furthermore I should to be allowed to drag and drop the cards in the second deck. My problem is that I can't drag and drop a card from second deck until the first deck was refilled a first time and I don't understand why. This a simple example project with a one card stack: https://mega.nz/#!r0IWWYwa!NDgO11BO8UzeZuSsVP2v6OBKlU25RLOf6pk1nFf2tJ0 I hope somebody could help me, because I really don't understand this very weird behaviour.