If you do not know if you have already created an account, you can check by signing up.

You will be prompted by "Email has already been taken" message if you have an existing account. 

If this is the case, you can reset your password by 

1. Clicking on "Forget Password" link

2. Type in your Email address > Click on "Reset my password"

3. Check your inbox for the instruction to reset your password

4. Click on the link to reset your password

5. Type in your new password and click "Update & Log in"

Related article:

How to sign up to helpdesk portal