A refund is usually most realistic when the cancellation request is made early, travel has not started, and nothing has already happened that could give rise to a claim. Beyond that, policy terms and route-specific rules matter.
Support will normally need to know the issue date, whether travel began, whether any medical or travel incident has already occurred, and whether any benefit has already been used. Those are the basic facts that shape a refund answer.
The best way to ask is with a short, factual timeline rather than a general complaint.