If you have forgotten your password, you will be able to reset it using a password recovery link. This can be done from the login screen by clicking on Reset password.
Enter both your username and email address. The email address you enter will be the email address used to send you the recovery link. Finally, click on Send recovery link.
You will receive an email with a link that will allow you to change your password. You can then re-attempt to log in with the new password you have set.