Hello there, hvanzyl.

You'll want to create a Refund Receipt if your customer asks for a refund for an item or service. Record a refund to your customer using Cheque or Expense if they want you to reimburse an accidental overpayment or want to redeem their open credits. 

If they chose the first option, here's how to create a refund receipt:

1. Select + New and click Refund receipt.
2. Enter the customer you want to refund.
3. Select the bank you deposited the payment for the invoice under the Refund from drop-down.
4. Add all products or services to the customer. Review the amounts and items.
5. Select Save and close.

For more details on how to handle customer refunds, just click here. 

If you have other questions, please don't hesitate to post them here. Take care!