Once you have connected a music account to Soundiiz, depending of the platform, Soundiiz could display some "generated" playlists. These playlists are only viewable on the Soundiiz interface. They are not existing for real in your music account. That's why you can't rename/udapte/delete them.
These playlists could be useful and are populated with your music account data (for example a playlist with your favorite tracks, your recent listening history, your top tracks of the month...).
If you like them, you can use "Clone" feature to save them into your music account (for real this time), convert them to another platform or Sync them with the Synchronization feature.