How do I approve or deny a refund?

Open the tournament and go to the Players page — it covers roster, payments, and refunds. Set the Refunds filter to "Refund eligible" to see who's awaiting a decision; the Players nav item shows a badge with the pending count.

From a player's row (or a bulk action) choose to issue the refund through Stripe or decline it. Depending on the tournament's refund policy, some refunds are auto-approved on withdrawal and need no action from you.