To create a refund :

  1. Go to Transaction window by clicking Transaction button on the top menu bar
  2. On the left sidebar of the Transaction window, select the date where the original sale transaction occurs
  3. Select the intended sale transaction on the right table
  4. Right click on it and select Refund
  5. Enter a reason for the refund
  6. Click continue
  7. A reverse sale transaction will be made on the date you make the refund

Note that the reverse sale will be created at the day when the refund is made. So if you are refunding a sale made one week before, the reverse sale will be created today and the negative amount will be counted towards today's aggregate sale amount