When trying to transfer playlists to Amazon Music or create a new playlist in Amazon Music with Soundiiz; you could have an error message, often with code error 304.
Important: Only "paid" members to Amazon Music can create personnal playlist in Amazon Music. Free tier users of Amazon Music can't create such playlists and will get an error while trying to convert playlists to Amazon Music with Soundiiz.
Even if you are a paid subscriber to Amazon Music, be aware that this could happened time to time and it's mostly not an issue with the title of your playlist or special characters. But simply a temporary issue with the Amazon Music API.
We recommend you to try again later. If still not working, it's possible that is an issue with your Amazon Music account; nothing can be done on our side on this point. We recommend you to reach Amazon Music support to see why there's such issue with your Amazon Music account and the Amazon Music API.
Thank you for your understanding.