On my F62 (manufactured 2021-05-23) all the keys work except for the right Shift.  That key does not “click”, it just moves up and down without clicking and without sending a key-down event (or sometimes, it sends the key-down but not the key-up).  I have replaced the keycap a few times, holding the keyboard with the space bar uppermost and the keys facing away from me so that the spring settles near the top of its hole before replacing the cap.  Usually, while I continue to hold the keyboard vertically the key will work well.  If I lower it to an angle of 45 degrees tilted away from me then the key still works.  But with the board flat on my desk the right Shift no longer clicks.

I wondered whether the larger keycap was the issue.  Sometimes these big keys are more troublesome than the little square ones.  So I removed a square keycap (the right Fn) and put that in the place of right Shift.  Indeed, with the small cap it works, clicking up and down nicely.  Then I tried using the right Ctrl key, which is bigger than square but still not quite as long as the right Shift.  With that keycap installed in the right Shift position, it too works.

On the other hand, if I take the left Ctrl keycap, which I believe is exactly the same size as right Shift, and install that in the right Shift position, it gives the same problem of not clicking.  So the problem is triggered by the size of the keycap used.  Smaller ones work, but a full sized right Shift (or equally sized keycap) won’t activate the key properly.

I know I could open up the board and replace the flipper and spring entirely for this key.  But I see that as something of a last resort (and unfortunately, I left the spare parts behind when travelling, I only have the board itself for the moment).  Given what I’ve found, is there anything else you can suggest?  As far as I can tell the board is clean and there aren’t bits of fluff or gunge obstructing the keywell.