maybe you wrote the password wrong or smth... or you pressed wrong button and wrote it in cyrilic. it happend to me once or twice.
Really sad is, that there are people with powers (GMs, Devs) who could track the character and find out who the real owner is. I mean if one character is used by one IP and suddenly at one day another IP starts to use it, it's very suspicious. Don't tell me you don't have these logs, when a player is online you probably see at least his IP (reminds me ban-happy GMs checking for same IPs to catch fast-reloggers in the past).When it comes to banning people, every GM works hard, but when it comes to helping people, nothing is really happening, so typical. But I guess that's a human nature.
I mean if one character is used by one IP and suddenly at one day another IP starts to use it
So actually he wouldn't be able to connect via any of IP addresses used before the theft, am I right?