There should be transactions attached to your subaccounts for the balances to show on your Chart of Accounts. Let' me help make sure you add transactions to these specific credit card subaccounts.
You can try creating a sample Bank Deposit and choose the subaccount as your deposit account.
Here's how:
Go to Plus icon.
Click Bank Deposit.
Enter dummy information.
Click Save and close.
You can check your Chart of Accounts and see how balances show after creating the deposit. Once verified, you can delete the bank deposit afterwards.
To delete a bank deposit:
Go to theAccountingmenu.
SelectChart of Accounts.
Find the bank account holding the deposit and then
Select View register.
Search for the deposit and select it to get more details.