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You’ll usually encounter this message prompt if you have multiple accounts under the same financial institution. Make sure to link the parent first when setting a hierarchical bank or credit card. From there, add the individual cards as sub-accounts.
Follow these steps:
From the Accounting menu, select Chart of Accounts.
Click the Account history drop-down under the Action column and pick Edit.
In the Account window, place a checkmark in the Is sub-account box, then choose the parent account in the drop-down.