Here is a great example of how Spotify deals with it.
I love how they try to change your mind until the very last moment. They don’t make it difficult for you to cancel your account but they play with your emotions.
This is the message you see when your are about to take the last step to unsubscribe from Spotify. Check out the song 😀
How cool. I think this a is great example of how you can reduce churn/ increase retention among your users. Make it personal, play with their emotions, make it funny.