Hello, accounting609. I can assist you in modifying the product and service on your customer invoice while maintaining the same amount.

When it comes to changing products and services, it's important to ensure that all the necessary details are accounted for before making any modifications. Specifically, you'll want to ensure that each product and service you modify includes the sales price or rate amount. By doing so, you can rest assured that any changes you make to the invoice won't result in unexpected fluctuations in the amount. 

To edit a product or service item, here's how:

1. Click the Gear icon and select Products & services.
2. Find the product or service you want to change.
3. Choose Edit in the Action column.
4. Make your changes.
5. When you're done, select Save and close. 

The sales price or rate amount refers to the cost of each product or service. This information is typically included in the product or service description, and it's essential to double-check that it's accurate and up-to-date before making any changes. Once you've confirmed this information is entered in the product and service and the issue persists, I suggest opening your account using an incognito/private browser.  

This may have something to do with your browser cache-related issue in your account. Your browser saves files to load websites faster on your next visit. But over time, it'll get outdated, which can cause performance or display issues using QBO.

• Press Ctrl + Shift + N (Google Chrome)
• Ctrl + Shift + P (Firefox)
• Control + Option + P (Safari)

After signing in, proceed to create an invoice. Make sure to change the product and service before doing so. Check if the invoice still displays zero amount. If it does, return to your default browser and clear the cache. This should help eliminate any temporary files that may be causing QBO issues. To do this, go to your browser's settings and look for the option to clear browsing data. Usually, you can select the time range for which you want to remove the cache and cookies. 

Also, you must ensure you're using a supported browser. QBO works best with Google Chrome, Mozilla Firefox, and Microsoft Edge. If you're using a different browser, switch to one of these supported options to see if it resolves the issue. If you're still having trouble, try turning off any browser extensions or add-ons you may have installed. These can sometimes conflict with QBO and cause issues with its functionality.   

See this for more information: Add product and service items to QuickBooks Online. 

You can also check this page to learn more about tracking your inventory in QBO: Set up and track your inventory in QuickBooks Online.

Please click the REPLY button below and mention my name if you need further assistance. You can also post here again if you have any additional QuickBooks-related concerns. It'll be my pleasure to help you out again. Take care, and have a good one.