Let's make sure to include the cost credit on the mapping expense in your 1099 Wizard.
You have the option to select and map the correct expense account of the transactions. Also, you can only map the expense account of 1099 on box 7 supported by QuickBooks.
See these articles for detailed guidance: QuickBooks 1099 Wizard
Feel free to read this article frequently asks questions about 1099: Common Questions About 1099s.
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