Windows 10 May 2020 Update started rolling out to customers worldwide on May 27. Not everyone can immediately update their devices to Windows 10, version 2004. Windows 10 2004 is being delivered as part of a phased rollout process to a limited set of customers with devices running Windows 10 versions 1903 and 1909 known as “seekers”” Microsoft has also started training a machine learning (ML) based rollout process for automatically updating Windows 10 devices approaching their end of service. Microsoft recommends not to attempt to manually update devices until these issues have been resolved.”
Source: https://www.bleepingcomputer.com/news/microsoft/windows-10-2004-list-of-compatibility-issues-blocking-updates/