Upload Customers from Spreadsheet - Customer Bank Account sheet

Summary

Having trouble figuring out how to create Customer Bank Account when creating the Customer

Content

We're using the Upload Customers from Spreadsheet functionality to create Customers in Fusion Receivables.  We have to create bank accounts for many of them, which is used to identify the Customer in lockbox AutoMatching.  However, we're having trouble figuring out how to populate the spreadsheet appropriately.  The Customer Account & Site gets created, but not the Bank Account.

The spreadsheet indicates Bank Name and Bank Branch Name are required.  That's not a problem, we always create them prior to creating the accounts.  However, the spreadsheet also says the combination of Bank Name & Bank Branch Name must be unique.  We have several customers who use the same Bank & Bank Branch.  We're not able to figure out what Oracle is validating here.