See full return policy here
How do I return or exchange an item purchased using Afterpay?
If you have changed your mind, you can return your Afterpay purchase in-store or by mail for a refund. Please check that your return or exchange meets our Return policy here. Afterpay will be notified of your return and will process the appropriate refunds. Please do not return your purchase to Afterpay.
If you believe there is fault or concern with your Afterpay purchase payment, please contact Afterpay customer support at firstname.lastname@example.org.