First, the merchant has to process the refund in their system. The refund will then drop through to reflect on your Afterpay account, and if you're owed a refund back to your card, it will be returned to the card that was used to make the payments.
Once processed, the money can take up to 10 business days to be returned to your card/s, depending on your financial institution.
It is important to remember that returns are always subject to the merchants refund policy. This information can normally be found on their website or by contacting the merchant directly.
Take a look at this video below!