Hi there, Doreen1977. 

We're unable to adjust A/R balances without tagging a customer in QuickBooks Online. You can also create a Journal Entry to correct or adjust the balance. Here's how:

1. Click the + New button in the left-hand corner.
2. Select Journal entry under the Other section.
3. Enter all the required details and click Save.

However, we recommend reaching out to your accountant prior to creating an adjusting entry since this will affect your financial reports. 

You can always add another reply below or post another question if you need anything else.