Hey @Mat Éo If you want to subscribe through Deezer directly, cancel your subscription on your iPhone, iPad, or iPod touch by doing as follows:

• Go to Settings > iTunes & App Store
• Tap your Apple ID at the top of the screen
• Tap View Apple ID. You might need to sign in or use Touch ID.
• Tap Subscriptions > Deezer
• Tap Cancel Subscription

When your Deezer account reverts to free (you’ll get ads), subscribe again to Deezer Premium but via dzr.fm/offersPremium on the web browser of a PC/Mac.

Don’t worry! You won’t lose your playlists and favourites!

Let me know if you need further help :)