Hello, @Pitarra. 

Let's resolve the error you're having when trying to use the new layout for invoices. 

The problem you're having with your invoice's layout going back to the old layout can be caused by the piled-up cache in your regular browser. It stores temporary internet files from your browsing history. As it collects too many files, it can cause some issues in your account.

I've got some steps to help fix this issue. First, sign in to your QuickBooks Online (QBO) account using a private browser. This helps isolate the issue since it doesn’t store data in the cache. 

Here are the following keyboard shortcuts: 

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

If it works, here's how to clear cache and cookies to fix issues when using QuickBooks Online. Restart your browser right after. You can also try to check with other supported browsers (Firefox, Google Chrome, Safari, Microsoft Edge) if the steps above don't work.

Here's additional information about letting customers pay you via credit card, PayPal, Venmo, or ACH transfer: Connect your QuickBooks Payments account to QuickBooks Online. 

Let me know if you need more help with your invoices or anything else. I'm always here to assist. Have a wonderful day!