How to apply a credit note

How to apply a credit note to an invoice.

In the Receipts or Payments journal, select a customer or vendor.
Click in the Amounts column on the credit note (the figure in red).
Click the Amounts column of the invoice you want to be paid, make sure the amount is equal to the credit note.
Process the transaction.
If you need to remove a credit note, see How to remove a credit note or deposit for a customer? instead.