Activate it for your account here:
https://www.paypal.com/webapps/mpp/returns
This complimentary service is now eligible for 12 purchases (used to be 11).
Refund requests must be sent within 14 days of returning item. Return shipping cost will be refunded to your Paypal account within 5 business days after approval.
Full terms and conditions:
https://www.paypal.com/us/webapps…urns/terms