Cortana service is no longer supported in Microsoft Launcher.
Unfortunately Cortana service is no longer supported on Microsoft Launcher. However, you can still access Cortana services with the latest version of Windows 10. For more information, please see the blog post here: https://blogs.windows.com/windowsexperience/2020/02/28/cortana-in-the-upcoming-windows-10-release-focused-on-your-productivity-with-enhanced-security-and-privacy/