i constantly had this issue trying to create a character too this week. I finally after 1 week of waiting was able to create my first character early this morning but the last 6 days of trying when i would catch a server supposedly allowing new characters i would get the error the op is talking about. I think when that happens someone has already beaten you to making the available characters on said server and it defaults to that message since the world is full and character creations were locked again.