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Service Management automatically creates a credit memo when a service invoice with a negative total is saved.
Invoices become negative when a returned inventory item is posted through Sales Order Processing, when a credit memo or return is posted in Payable Management, when adding negative costs using the "+" button, when adding an inventory adjustment with a positive quantity, and when creating a negative payroll transaction through TimeTrack. See Entering Inventory Transactions using SOP, Entering Manually Added Transactions, and in the TimeTrack User Manual.
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