Thank you for sharing your situation on this thread, @KN52. I want to help you apply the total credit card payment to the individual balances of your sub-accounts. That said, I'll share some insights to get this sorted out.

You need to know how your bank sends the downloaded transactions before connecting to Online Banking. You can only connect the parent account if the transactions download to one account. Otherwise, you'll need to connect the subaccounts if the transactions are downloaded to individually.

When you connect your account, the same opening balance transaction may be downloaded to all subaccounts. This means they can be similar. At the subaccount level, certain banks may display the total bank balance. This is because the bank provides us with a static balance of the entire account, not the balance of each subaccount.

Take note that when reconciling, you only need to reconcile the parent account. This is because all the transactions in the subaccounts are wrapped into the parent account.

You can refer to this article to learn how to reconcile your account in QuickBooks Online.

Please know that I'm here anytime you have other banking concerns . We'd like to make sure this is resolved for you. Take care