You may have the need to unmap items between D-Tools Cloud and QuickBooks (Online or Desktop).
In D-Tools Cloud, click Catalog and then My Products.
Choose the product you wish to unmap to open it for edit.
Scroll down to the bottom of the edit window and in the Integrations section, click the ellipse and then "Unmap product":
If desired, you can then go delete the item or mark the item as "Inactive" in QuickBooks.