There is a Security Setting that may be activated by the Manager of the account. This setting will require you to have an Authentication Code emailed to yourself to verify your identity.
When you have added your login details you will see the below
You will get the following email sent to the address stated above
Enter in the code within the email into the login page. Please note - this code expires within 10 minutes.
Click Submit Code. This will then let you continue to login to your account.
If it doesn't work, or if the code has expired, click Resend Code to try again. Please ensure you use the code from the most recent email.
The email also confirms the Managers email address. You can contact them if you're unable to login and they will be able to remove the setting and assist you.