If you receive this error first make sure that the data in your import file is correct read more on our blog
If you are QuickBooks Global user (eg non US) Intuit has responded this is a bug in the QuickBooks Online API. Details of the bug are: There is an existing bug on similar issue, QBO-49304
. Bill that has multiple line items with the same tax code, needs a TxnTaxDetail attribute. If not it throws a Business Validation Error.
Intuit has indicated that they have asked their Engineers to review this bug. We do not know at this point when this will be ficed in the Intuit QuickBooks Online API. Our support incident number with Intuit is 00029069.