A refund did not show up in WooCommerce
WooCommerce is updated once Paddle approves the refund, which can take a little while. Classic accounts also need the Payment Refunded alert (and Subscription Payment Refunded for subscription payments).
Renewals or cancellations are not reaching WooCommerce
- Billing: click Set up webhook for the current mode.
- Classic: enable the subscription alerts.
A webhook arrived twice, or out of order
That is normal for Paddle, and the plugin is built for it: payments, renewals and refunds are never recorded twice. Developers can read how in Concurrency and idempotency.