You can add the items from the invoice to the credit memo manually, Alexis. I have insight about this, and I'll explain this to you.

When adding items from an invoice to a credit memo in QuickBooks Online (QBO), it's important to note that you can only do this by hand. Unfortunately, there's no direct way to copy the items from the invoice to the credit memo. For each returned item on the invoice, you'll need to create a separate credit memo transaction.

Furthermore, to effectively manage your sales within QBO, you can utilize the reporting features to track your business's performance and transactions.

Once you've applied the credit memo, don't hesitate to comment if you need further help. We're here to support you in any way we can. Have a good day!