Log in to the Storefront Admin
Click Orders | Manage Orders
Enter the Order Number in the Search Field and click Apply Filter
Click the resulting Order Number to Open the Order
Scroll down to Order Processing Actions
Select Force Void and Click Submit
In the resulting window Click Yes
This voids the Credit Card transaction, which in turn, stops the order from importing to Sage.
After completion, it's important to mark the FreshDesk Order Ticket Closed