Hello gloriadeb204!

The reason why it shows positive and negative lines is because of the method you used, the journal entry. Let me show you how to properly write it off as bad debt.

Based on the screenshot, I'll assume you already have an expense account to track the bad debt. If so, proceed to these steps:

1. From the Customers menu, select Receive Payments.
2. Select customer in the Received from drop-down, and enter $0.00 in the Payment amount.
3. Click the Discounts and credits button. 
4. On the pop-up, enter the amount you'd like to write off in the Amount of Discount field.
5. For the Discount Account, select the bad debt expense account.
6. Tap Done, then Save & Close.

Once done, pull up the A/R Aging report again to verify.

Need more references on how to manage your business in QuickBooks Desktop? Check this link: QBDT All Articles.

Leave a reply below if you more of my help. I'll be here!