The "D" key on my MBP has suddenly stopped working normally. It will type if I press firmly in the center of the key and it seems to work with normal force if you hit the key on the very corners but a normal press in the center of the key does not work. I popped the key off to see if I could clean it and that didn't help so I popped it off again and then popped off some other keys and noticed a difference. Please see the attached photo. The D key is missing the black part that is present on the other keys. What is that? Where could it have gone? Can the entire butterfly assembly be replaced?
TIA
TIA