Can you add the product/services fields to journals in QuickBooks? How can you correct a mis-posted invoice that has the wrong product or service?

It's a pleasure to have you here, @david-treesforli. 

We can edit the invoice that has incorrect products/services. We simply open the transactions and edit the products/services. 

Here's how:

1. Log in to QBO.
2. Select the Sales menu on the left panel.
3. Choose Invoices and click the invoice that has the incorrect products/services.
4. Click the Edit button. 
5. Make the necessary changes and click Save and Close.
   
   

I'm also adding these articles to help manage your invoices in QuickBooks Online: 

• Create invoices in QuickBooks Online
• Customize invoices, estimates, and sales receipts

Feel free to leave a comment below if you have further concerns about changing products/services on invoices. I'll be happy to help you always. Keep safe!