Have you made sure you're using the exact same player name you were using before? Remember it's case sensitive.
If you're sure you're using the same name, you might have to contact Soren directly to get help and recover your character, with forum PM.
Normally your account should still be there and your character should still be there in the same state you left them last time you played since those are never removed. Check carefully as this is likely a typo mistake.