You must have an account created for you, to be able to log in. The easiest/quickest way is to ask someone in your organization who already has an account, to open a support issue.
The first time you log in to this portal, you need to Request a new password, giving the user name you have receieved. This will send a mail with further instructions to the email address stored for your account in Issue Tracker.
Looking for BSS/Billiant Support? Click here instead.
Contact email@example.com for help with existing accounts, etc.
The way to get an account is to have someone in your organization who already can access the support portal, to create a support ticket, containing your name and email address.