After you registered your account, you have to verify your email address.
A verification email is sent your email address right after the registration.

If you have not received this verification email, you can request another one in your account profile at https://universe.flyff.com/profile .

However, some email providers might not be suitable for receiving these verification emails.
If you experience issues with receiving the verification email (even after requesting new verification emails in your account profile), we recommend to try another email provider to register your account (e.g. GMail).