A learner will show as 'Not registered' on the learner progress page if they have not actioned the registration email sent to them when they completed their assessment. This allows them to set up a password and log in to their account.
To resend the registration email, click on the learner's name in the learner progress window, then click 'Learner details'.

Then click 'Resend registration invite'.

This will send the learner a new registration email to set their password for the first time.
Learners should check their junk/spam folder if the email does not arrive in their main inbox.