Mistakenly Marked A Game As Received

I was checking on Steam Gifts when I saw that I won a game. So, I talked with the giver to receive my prize. When I returned here to mark the game as received, I accidentally marked another game as received. It was the first time that I got two games on the same day, but I did not realized that until after I marked the second game. Does this mean that the second giver can simply move on with giving their game?

Edit: Thanks for the help. I got the second game unchecked now.