There is a user here who keeps posting auctions for items which are not available. It has happened to me three times with him. Finally, on the third time I got tired of it and gave negative feedback so as to warn others. Six weeks later he has logged on and given me my first negative feedback received on this site (and only the second one ever anywhere, the other being for the same reason). This seems very unjustified to me. Is it possible to appeal this feedback?