I can see that you were visited by ghosts/gremlins - I have several living in my sewing area. That would have to explain why I can put something down, a block, a pair of scissors, rotary cutter, the list is endless, then when I go to find it, it has "flown the coup". I can only find it if I make another block or reach for another scissors, rotary cutter, whatever. I guess it's one of the "joys" of getting older. LOL. Just know that you are in good company and that when you make another block you will find the missing one - Murphy's Law of Quilting.