Thanks for chiming in, @DianaDe. I'm here to help you keep the process of writing off-invoice balances easy and simple.

When invoices you send in QuickBooks become uncollectible, you need to record them as a bad debt and write them off. This ensures your accounts receivable and net income stay up-to-date.

Here's how: Step 1: Check your aging accounts receivable:

1. Go to the Reports menu.
2. Find and open an Accounts Receivable Aging Detail report.
3. Check which outstanding accounts receivable should be written off.

Step 2: Create a bad debts expense account:

1. Go to Settings ⚙ and select Chart of Accounts.
2. At the upper right, select New to create a new account.
3. From the Account Type ▼ dropdown, select Expenses.
4. From the Detail Type, select Bad debts.
5. In the Name field, enter “Bad debts.”
6. Select Save and Close.

You can take a look at this article for the detailed steps (proceed to Step 3):  Write off bad debt in QuickBooks Online. This will provide you steps on how to manage uncollectible invoices in QuickBooks.

Additionally, you can visit the following write-up: Sales and customers. This will provide you links on how to manage your company income as well as resources about other customer-related concerns.

I'm only a post away if I can be of additional assistance or need more help with QuickBooks. I'm always here to keep helping. Wishing you a wonderful rest of the week.