Re: [[:vi:Thảo luận Thành viên:mxn/2014#My user name|My user name]]
Some of the original blacklisted user name patterns were references to Ho Chi Minh, or "Bác Hồ". Someone was getting around the patterns using something like "Pác", leading to the entry that affected you. Of course, that was 2008, long before Single User Login, so I've amended the entry to allow your user name. Sorry for the inconvenience.