Welcome to the Community space, Miriam.
There are several possible reasons why some Shopify sales don’t match items in your clearing account.
One reason could be that the transaction was processed through a payment gateway other than Shopify Payments, such as PayPal or Stripe. If this is the case, your integration may not be configured to route these sales through the clearing account, and instead, they could be going directly to a different bank account in QuickBooks.
Another possibility is that your QuickBooks Online integration is set up to record individual sales as they occur, posting them directly to your main bank account instead of the clearing account.
Lastly, there may be a misconfiguration in your sync settings. For example, a rule might be set to automatically "add" or categorize certain transactions, bypassing the matching process.
To confirm and address these issues, you can reach out to the Shopify Live Support team. You can find their contact number in the Contact section of this link: Shopify Connector by QuickBooks.
If you have any additional questions, feel free to revisit this thread.