Here is how you update and resend the email or reassign the existing order to a new candidate:
When viewing your applicants in the “Applicants” tab on the left-hand side
Click the Resend Email to the right side of the applicant row or the box with the three dots
A window will pop up where you click "Resend or Update Email"
Click Update & Send Email, the email will be resent to the email address
If you reassign the order to a new applicant's email address, don’t worry! The old link sent to the invalid or old email address will be disabled.