i cant use the top row in my inventory

so it was a normal minecraft day i was mining and i ran out of torches so i go in my inventory to get some torches i reach the top row and try to get some torches i click the torches and drag the torches and the torches didnt follow my mouse so i try again it dosent work i reset my world it still dosent work i reset my game and i still couldnt get any items on the top row. if you know what is happening please fix it in the next snapshot becuase its really annoying.

thank you