Item in hotbar drops from my inventory out of nowhere

When playing recently on minecraft creative mode, items in my inventory just drop as if I'm doing it. When it happens, you can see the green bar filling up on the item that it happens on and it's always the first item in my inventory. It's not my console because it did it to me cousin too when we were playing on her world and just a few minutes ago on my other cousins world when I was putting torches down and it kept dropping when I was putting them down. Please fix this as it is not practical to keep repeatedly picking up the items I'm using.