Most times if I ask for an undo request it is granted, and i always do the same for other players. Recently I played a game where I did an obvious misclick, that did not reveal anything, and my undo request was denied. I repeatedly put in the request, and it was denied, and then mysteriously it looked like I resigned, which I did not. Maybe it timed me out? Also, what is etiquette in the case of undo request? Is it okay to blacklist someone for this denial?