Cancellations rarely start as cancellations. They start as "can I skip next month", "can I swap the flavour", "can I change my delivery day" — questions where a fast, accurate answer keeps the subscription and a slow one ends it. Those are all policy answers, available day and night, which is precisely what a retrieval-based chat is good at.
Two details make the difference between a save and a churn. First, the answer has to be specific: "you can skip up to 48 hours before your renewal date, from Account then Subscriptions" beats "yes, you can skip". Second, if the customer wants it done rather than explained, the handover has to be immediate and honest about timing, because a promise of "someone will get back to you" without hours attached is how a skip becomes a cancellation.