I understand the importance of using the quantity in invoices, darrellsautorepair. Let me help you so that you'll be able to use this feature again. 

Since you've mentioned that the only available columns were Product-Service, Description, Amount, and Tax, I suggest using a private browser to eliminate any potential issues caused by browsing history or cache files. Below are the shortcut keys for accessing private browsing:

• Google Chrome: press Ctrl + Shift + N
• Mozilla Firefox: press Ctrl + Shift + P
• Microsoft Edge: press Ctrl + Shift + N
• Safari: press Command + Shift + N

In addition, you can clear your browser's cache and cookies if this matter continues. You may also use other supported web browsers to help identify if the issue is related to your current browser.

If you're still unable to see the quantity column within your invoices or with the other sales forms, you'll need to reach out to our QuickBooks Online Support. This way, they'll be able to identify the root of the problem and provide you with the best possible solution. 

Should you have any additional assistance regarding invoices, feel free to enter your concerns in the comment section or reach out to the Community. We're here and prepared to offer our support.