Nostalrius Begins - Quality wow vanilla realm (1.12)

Hi all,

I can´t creat my Nostalrius account
Each time I type in my dates and press register (at https://en.nostalrius.org/register) it doesn´t work.
The error is: Registration failed! Bad credentials.

What does that mean?

Please Help!

Your username may be too short. Try having a longer username, at least six characters.

Das Troll