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Most likely you are thinking of a procedure where first the key (that you touch) is pulled up and out of the keyboard, then the space that reveals allows you to reach in and reset or reposition the key-switch's parts.
However, if the dropped key in this case is the same exact note, it might be well to consider replacing the keyswitch also, before the problem becomes so frequently recurrent as to make the stress on the parts, of going through the same remove-reset-replace procedure over and over, that other parts aside from the keyswitch break too.