I answered a question regarding pistons in minecraft and how to control them individually. What I didn't see was that he later commented that they were vertical, however, he never edited the question.
Long story short I answered the question (and put a lot of effort into the answer) and then the asker commented that it was vertical, not horizontal. So I posted a comment that said To wait one moment (to avoid downvotes). However, someone completely ignored that comment and downvoted anyway without leaving a comment as they should have and I lost 2 rep points.
I know it was only two rep points but still.
So my question is, how can I notify the person to re-vote my answer?