The customer authorization (provided in the link you clicked) is out of date, and does not entitle you to use the Blended Threat service.
https://www.gov.uk/government/publications/no-deal-readiness-report?utm_source=ffe08297-4fc9-43e8-b793-c6757aa563ef&utm_medium=email&utm_campaign=govuk-notifications&utm_content=immediate