It's a pleasure to have you in the Community today, @aseiberlich. I've got you covered, and let's work this out so you can get through this and change the product or service item on the invoice in your QuickBooks Online (QBO) account without clearing the information in each field.

Before we start, please be aware that the feature you're trying to access in QBO is unavailable. The product or service item's description, rate, and amount depend on how its created. To change the product or service without affecting the information in each field in your invoice. You'll need to set up a different product or service item using the same information you have in your previously added items. To begin, here's how:

1. Go to Get paid & pay or Sales, then select Products and services.
2. Click New, and then select Non-inventory or Service.
3. Enter a Name for the product or service and a SKU, if you track them.
4. From the Category ▼ dropdown, select the category that best describes your product or service. Learn more about item categories.
5. If you sell the item, confirm the checkbox is selected for I sell this product/service to my customers.
6. In the Description on sales forms field, enter a description. This is what your customers will see on their sales form.
7. Enter an amount in the Sales price/rate field. Note: If you charge a variable rate for services, you can leave the Sales price/rate field blank. Then add the price when you fill out the invoice or sales receipt.
8. Select the Income account ▼ dropdown and the account you want to use to track the sale. Tip: You can use an income account QuickBooks already set up for you, or select + Add new to create a new income account. Learn more about adding accounts to your chart of accounts.
9. In the Sales tax section, sales tax is applied by default based on location. For more specific options, or to make the product or service nontaxable, select Edit sales tax. Then do one of the following, depending on the product or service:

• If the product or service is tax-exempt, select Nontaxable. Then select Done.
• If the item has a special tax rate, use the Search field or Browse all to find and select a more specific product or service type. Then select Done.   

       10. When you're done, select Save and Close.
 

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

In addition, I've got you this article to help you manage invoice payments in QBO: Record invoice payments in 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.

@aseiberlich, if you need further assistance with this, feel free to click the REPLY button below and mention my name. 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.