The customer authorization (provided in the link you clicked) is out of date, and does not entitle you to use the Blended Threat service.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/guidance/changes-to-international-trade-mark-registrations-after-the-transition-period?utm_source=69a9213c-d0c7-4b79-8e6e-18222388a9b8&utm_medium=email&utm_campaign=govuk-notifications&utm_content=immediate