https://www.techradar.com/news/microsoft-kills-groove-music-on-android-and-ios

Microsoft is continuing to purge Groove Music from its system, and today announced that it's killing off the service's apps on Android and iOS.

The apps are no longer available to download, though if you already have one installed you'll be able to keep using it to play tunes stored on OneDrive until December 1, when the apps disappear to the great SD card in the sky.