I'll ensure that you can correct your invoice number fields in your account as quickly as possible, @Wilson74.

I'll walk you through the complete steps on how to remove the WOO in your invoices in QuickBooks Online (QBO). 

If you're referring to the screenshot below, I recommend you manually delete the WOO to eliminate it from the sales forms. Let me point out how:

1. Go to the Sales tab, then select Customers. 
2. Click the appropriate name. 
3. On the Transaction list page, tap the exact invoice. 
4. Edit the Invoice no. field, then click Save and close. 

But if that's not what you're referring to, would you be able to provide us with a screenshot of your invoices? This way, I can give you the exact solution to remove the WOO on your sales forms.

For your future reference, check out these articles below on how to send invoice reminder messages, personalize sales forms, and run customer reports in QuickBooks: 

• Customize invoices, estimates, and sales receipts in QBO
• Send invoice reminders automatically or manually in QuickBooks
• Reports included in your QuickBooks Online subscription

I look forward to hearing from you, Wilson74. Keep safe and healthy.