1. Contact Lighten's after-sales customer service and explain the reason for the refund.

2. Provide purchase vouchers and relevant certification materials.

3. Wait for the after-sales customer service to review and confirm the refund.

4. Return goods and refund according to the instructions of after-sales customer service. It should be noted that the refund process may be different due to different regions and products. Please refer to Lighten official website or after-sales customer service guidelines for specific operations.