Hi there, anne. I'm here to help you switch to the old template.

Changing to the old interface in QuickBooks Online (QBO) is quick and easy. I'll show you how:

1. Go to the Gear icon and choose Custom form styles. 
2. On the New style dropdown, select Invoice. 
3. Under the Design section, choose Change up the template. 
4. Change your invoice template. 
5. Click Done. 

You can refer to this article for more info: Customize invoices, estimates, and sales receipts in QuickBooks Online. 

However, if you're referring to the old invoice layout, know that switching to an old invoice layout is available to selected users as of today. 

To switch to the old invoice layout, follow these outlined steps: 

1. On the left Navigation Panel, select New.
2. Under the Customer column, choose Invoice.
3. In the upper-right corner, click the Old Layout button.
4. Then, Leave. 

Here are more details on how to receive and record invoice payments in QBO: Record invoice payments in QuickBooks Online. 

Let me know if you have more questions. We're always here to help. Stay safe!