We get an error when processing credit cards, sometimes. We use merchant E solutions as a processor. To get the card to work, we have to uncheck the 'send line level data' box, then it works. There must be something in a field on the affected item records. I cant find what fields are considered in sending this data to know what to edit.  Our credit card processor says: This message means there is something in the line item detail (line level data) that is incorrect. When you uncheck Send Line Level Data, this skips sending the line item detail to MerchantE letting the transaction go through. Have you noticed a pattern of a certain line item on each transaction? If you can determine which item is causing the error you could fix the issue in NetSuite.

Try creating a payment event saved search. If you can find the payment events for failed transactions, you'll probably be able to see raw request and response data. Most likely issues are non-standard characters in product descriptions (esp. ™, ®, etc)