Deezer has recently implemented anti-abuse systems. If their servers detect a third-party downloader using your ARL, they will respond with a 403 Forbidden error or silently expire your token. You would then need to log in again to generate a new ARL.
The ARL token functions as a "digital ID card" that bypasses standard login prompts. It is stored as a cookie named Deezer Arl Premium
To use your Premium account with third-party tools, you must manually extract the ARL from a web browser where you are logged in: Deezer has recently implemented anti-abuse systems