Let me give you an insight into why you can't find them, @anderson4728.
There's a possibility that your previous customers have been inactive that's why they didn't show up on your end. To make them visible, all you have to do is tick the Include inactive option from the Gear icon in the Customers tab. Here's the step-by-step process:
- From the Customers & leads menu, select Customers.
- At the top of the ACTION column, click the Gear icon.

- Scroll down and check the box for Include inactive.

Additionally, you can refer to this article for guidance on creating invoices: Create invoices in QBO.
Furthermore, if you want to streamline your reporting process and get the most out of QuickBooks, don't hesitate to contact our Live Expert Assisted team! Our experts are always ready to provide guidance and support, ensuring you can confidently navigate and optimize QuickBooks.
Please keep us posted regarding any additional concerns in managing your customers.