I appreciate you for sharing your concern in the Community, @

Laura1980. I've got you some information about QuickBooks Online (QBO) Checking account.

When your clients signed up for QuickBooks Payments, they can get a QuickBooks Checking account and a debit card where all of their customer payments get deposited. 

Hence, the account won't automatically show up on the Banking page, until they link the account manually from there.

Here's how:

1. Sign in to QuickBooks, then go to the Banking menu at the left pane.
2. Go to the Banking page., then select Connect account if this is the first time setting up, or select Link account if you already created one.
3. In the search field, enter the name of your bank, credit card, or credit union. 
4. Select Continue. Then sign in to your bank with your user ID and password. 
5. Follow the on-screen pop-ups to complete the process.

You can also check out this article for an additional guide: Connect bank and credit card accounts to QuickBooks Online.

You also want to visit this link to learn more about the QuickBooks Cash accounts and its cash flows: QuickBooks Checking. 

Feel free to message again if you have other questions in mind. Take care!