Generate Expense Report PDF to File Cabinet

I’m trying to generate Expense Report PDF to File Cabinet by SuiteScript 1.0

function main() {
var filters = new Array();
filters[0] = new nlobjSearchFilter('type', null, 'is', 'ExpRept');
filters[1] = new nlobjSearchFilter('mainline', null, 'is', 'T');
var columns = new Array();
columns[0] = new nlobjSearchColumn('internalid');
columns[1] = new nlobjSearchColumn('tranid');
columns[2] = new nlobjSearchColumn('entity');
var searchresults = nlapiSearchRecord('transaction', null, filters, columns);
for (var i = 0; searchresults != null && i < searchresults.length; i++) {
var file = nlapiPrintRecord('transaction', searchresults[i].getValue('internalId'), 'PDF', null);
file.setFolder(14);
file.setName(searchresults[i].getValue('internalid') + searchresults[i].getText('entity') + ".pdf");
nlapiSubmitFile(file);
}
return JSON.stringify(searchresults);
}

Code above return error “UNEXPECTED_ERROR” without details.

It works fine with Type = CustInvc

Would anyone guide me how to generate Expense Report PDF to File Cabinet?

Thank you so much.