Welcome to HBH! If you had an account on hellboundhacker.org you will need to reset your password using the Lost Password system before you will be able to login.
Dear admins.
Mordak wrote: Have you tried using the reset password link ?
I think he meant that he doesnt use the email linked to the account, So he can't retrieve the password.
It seems like a lot of hasstle for the admins to need to recover accounts for people. It may be easier for you to gain access to the email you used to register.
If you have done the challenges before, then you shouldn't have any problems getting them done again. It may even be benificial for you to redo them, seeing as you refresh your memory of how you did them.