See if you can find the post that was supposedly removed. Usually when the violation email appeal link doesn't work (you get the "post didn't come from this account" message), it means your post was never removed to begin with. Your post is most likely still there.
You can always appeal question or answer removals here (as well as account suspensions):
and include The specific text of the post that was deleted, The violation reason specified in the notification email (if you got one, if you didn’t get one then make that known), The reason why you'd like it reviewed, and The Yahoo ID you're using in Yahoo Answers.
Bookmark that link for future use. In my experience, it provides better results than using the link in the emails (when you get them) anyway.