YouTube Music is a streaming service that offers both free and premium tiers. YouTube Music premium users are allowed to download music for offline streaming, yet the YouTube Music downloads are not saved as local files, they are stored as scattered cache files limited to be played on its platform. This means that even if you are a YouTube Music premium subscriber, you still cannot download MP3 files from YouTube Music because there are no local files stored on your device, only cloud-based cache files. The only way to get mp3 files from YouTube Music is to use a third-party service such as Music Downloader, which can help you save the cache files as local mp3 files on your computer.