Previous purchases

Thank you for posting here in the Community, Paul. I'm happy to help you to record previous purchases in QuickBooks Online (QBO). 

In QBO, you can add your purchase and record it as a bill or expense in QuickBooks. You can easily add the purchase order as a line item. This closes the original purchase order, connects it to the payment, and records the accounting accurately. Ensure to record purchases in order with the correct date. 

You can check out this article for additional guidance in recording historical supplier transactions. 

If you need to unlink a Purchase Order, check out this article for the detailed steps: Add purchase orders to expenses, bills, or checks in QuickBooks Online. On the same link, you'll find a write-up about when to use expenses or bills in QuickBooks Online.

You can always count on me if you need additional assistance and let me know how these steps turn out. I'm just a post away. Have a great rest of your day!