This is not the impression we want you to experience when using the forms template. I've got some steps we can perform to get this sorted out, 

River444.

Since you have full access to the company file, let's try opening another company file to check if you're having a problem with only one file and not the program itself. Let me show you how:

1. In your QuickBooks, go to the File menu at the top left.
2. Choose Close Company.
3. In the No Company Open window, click the drop-down arrow in the Open a sample file icon.
4. Choose another company file with an invoice template and click on it.

Then, try opening the template in the layout designer. To fix common template issues in QuickBooks Desktop, see the Fix common issues when you use and customize templates article. If it works, there may be a damaged data on the company file you've been working with. We can run the Rebuild Data tool is built-in to fix any company file data issues. Just follow the steps and detail in the Fix data damage on your QuickBooks Desktop company file article. We can also repair your QuickBooks Desktop to fix any damaged components in the software. 

If the problem persists, I'd suggest contacting our Technical Support Team. They'll pull up your account in a secure environment and investigate what's causing this issue. You may send a message via chat, call us at a time convenient to you, or we’ll get in touch with you instead. To ensure we address your concern, our representatives are available from 6:00 AM to 6:00 PM on weekdays and 6:00 AM - 3:00 PM on Saturdays, PST. See our support hours and types for more details about this one.

Feel free to visit our Sales and customers page for more insights about managing your company's income and customers.

You can always update us after contacting our support or performing the solutions, as I want to ensure this is resolved for you. Please reply to this post and I'll get back to you. You have a good one.