If you refund a payment outside of Salesforce, or wish to record a chargeback / return, we recommend creating a manual transaction record with a negative amount which references the Chargent Order. This will allow you to show a trail of Charges and Refunds.
Gateway Date=Date of the refund
Amount=A negative number
Gateway ID=Corresponding ID number or notes
Payment Type=The type of refund or chargeback
With a negative number, Type Refund, and Response Status=Approved, the manually created transaction will be deducted from the Transaction Total rollup field.