Quickbooks API / XML custom feilds

This is my first post here. I am using Quickbooks for windows to pass data to create a invoice which works all except the custom feilds that you create in quickbooks. I can't send values for the custom fields in my XML. I get this error. I would love a point in the right direction.

<?xml version="1.0" ?>
<QBXML>
<QBXMLMsgsRs>
<InvoiceAddRs requestID="143" statusCode="3180" statusSeverity="Error"     statusMessage="There was an error when saving a data extension named &quot;Shipper Name&quot;.  QuickBooks error message: The specified custom field cannot be used by the list or transaction element." />
</QBXMLMsgsRs>
</QBXML>

Here is the XML 80000006-1410484985 1642 Scott's Trucking 1004 Just sample data Isanti MN 90210 USA Mike's Trucking 123 dr Hayward WI 54843 USA From Exspeedite Shipment #1642 0 Shipper Name Bob COMMODITIES ----------- Freight of All Kinds (FAK) 3 pallets 3 items 1000 LBs Handling Handling charges 1 60.00 Freight Freight charges 1 4600.00 Mileage Mileage 2000 2.30 Fuel_Surcharge Fuel surcharge 1 1120.00 Other C104 - - Reconsignment 1 60.09 Other C104 - - Reconsignment 1 60.09 Other C118 - Inia Swan - Reconsignment 1 250.00 Other C122 - XSTOP2 - Reconsignment 1 30.00 Other C106 - - Layover 1 91.02 Other C107 - - Layover 1 11.76