Why are some people allowed to serial downvote? I have had the same person downvote me multiple times This is very discouraging. It seems like they should be reprimanded?
Serial downvoting is automatically reverted by an automated batch job when it exceeds the criteria set by SE. Looking over the stats on the backend, I can see that this has occurred in your case, at least in aggregate (we do not see individual votes).
Since we cannot review individual votes, mods do not take action based on user voting and we rely on the automated jobs to handle any problematic behavior. If you see comments or Q&A from users that violate our code of conduct then please flag that specific content rather than publicly posting here so that we may handle it on a case by case basis.