How do I revert to a previous version of a invoice that was wrongly copied?

Hi clark-dentallab7,

Thanks for posting in the Community! 

If an invoice was previously saved in QuickBooks Online, you can check your the Audit history. Audit History serves as a record of all the changes made on a specific transaction. In the Audit History, you can find the following information:

• Who made the changes.
• When the changes were made.
• What the changes are.

You can do that by clicking on More on your invoice and select Audit history or you can generate an Audit log report.

Here's how: 

1. Click on the Gear icon and select Audit log.
2. Select a date when the transaction was changed.
3. On Event drop-down menu, select All transactions.
4. Select View to see more details.

You can also check on this article for your reference: Use the audit log in QuickBooks Online. 

Let me know if you have any other questions and I'd be glad to help. Have a great day!