well I wiss i knew. Sometimes it will do that to me.
Maybe it is already used as a name?

you should check the name fill in your e-mail address so you
know what is your username. or you can try to make sure that
you didn't do like spaces or any mistakes or it can be a bug

I'm not too sure whether BaltoSource uses a confirmation
email system, but check your emails anyway for a
confirmation email. If not, make sure you spelt your
username and password right with the same details you use on
the main BaltoSource site.