If you create an item in ConnectWise PSA as InventoryPart, then we set the type in QuickBooks to "Inventory", and QuickBooks then requires track quantity on hand to be turned on.   If you don't want to track quantity then you should set the type in ConnectWise PSA to Service or OtherCharge (in which case we'll create it as a Service type in QuickBooks), or to NonInventoryPart which maps to QuickBooks NonInventory type. (this is intended for a physical part that you don't track quantity on)