About two months ago I was a victim of serial downvotes and as a result I was banned from asking questions on Math SE. I am still banned at the time of this post. It first showed me a warning that my questions were not well received, so I decided to take a break from asking questions. After that, someone decided to downvote almost all of my questions in a short period. That was the last nail in the coffin and I was subsequently banned. However, I think this is unfair since it really isn't my fault - fine, some of my questions were not well received, but the person who did this was responsible ultimately. I tried to flag a couple of my questions to tell the moderators what happened, but I got no response. What should I do? Any advice on this would be appreciated.