Confirm intent to cancel
Sometimes, users may accidentally click the destructive button that triggers the removal of an account or subscription. So prevent irretrievable actions by asking users to confirm their choice. Plus, it's an additional opportunity to try and reel users back by pointing out what they'll lose when they cancel the subscription. For example, if users can access the product only with a subscription, you can remind them of the product's value.
Conversely, if the product can be accessed in a free version, you can remind users of some specific subscription benefits. The golden rule here is to avoid using language that begs for sympathy or exploits tools of pressure or manipulation.