Thank you for your inquiry to the Community. We appreciate your decision to partner with QuickBooks Online (QBO) to manage your business operations. 

To provide you with the appropriate solution for your concern, we kindly request that you provide us with additional details regarding the invoice transaction. It has come to our attention that the item cost for your invoice in QuickBooks is reflecting an amount of $20, whereas it should be $10. To assist us in identifying any discrepancies, we kindly request that you furnish us with a screenshot of the transaction journal for the invoice created. This will enable us to ascertain the root cause of the issue and take the necessary steps to resolve it. 

To view the transaction journal:

1. Open the invoice in question.
2. Select the More option below.
3. Choose Transaction Journal.

You may find it beneficial to use the following articles, which can aid you in the monitoring and management of your inventory:

• Use reports to see your sales and inventory status
• What is FIFO, and how is it used for inventory cost accounting?
• Can I track inventory manually in QuickBooks Online?

We're looking forward to your response. Our team is always eager to provide you with the help you need. We wish you a prosperous year ahead with QuickBooks!