Enable WordPress debug logging in wp-config.php:
                define( 'WP_DEBUG', true );
define( 'WP_DEBUG_LOG', true );
define( 'WP_DEBUG_DISPLAY', false ); Check WordPress debug log at /wp-content/debug.log Search for "PayPal" entries to find payment processing logs Log in to your PayPal Account Go to Settings > Notifications Click IPN History Check recent webhook deliveries and status Click on a failed delivery for error details Click "Resend" to retry failed webhooks In PayPal Developer Dashboard, go to Sandbox > Tools > IPN Simulator Select an event type (e.g., web_accept for payment received) Configure sample payment data matching your test invoice Click Send IPN Watch WordPress debug logs for processing