Creating Free Text Invoice through X++ code

Job:
Calling class from job to run the class
public void freeTextInvoicePostTestJob()
{
Dialog dialog;
DialogField dlgCustAcc;
DialogGroup dialogPeriodLengthGroup, dialogPeriodLengthGroup1;
DialogField dlgLedgerAcc;
;
dialog = new Dialog("Free-Text Invoice");
dialogPeriodLengthGroup1 = dialog.addGroup('Cust Table');
dlgCustAcc = dialog.addField(typeid(CustAccount));
dialogPeriodLengthGroup = dialog.addGroup('Ledger Table');
dlgLedgerAcc = dialog.addField(typeid(LedgerAccount));
if(dialog.run())
{
if(dlgCustAcc.value() && dlgLedgerAcc.value() != '')
FreeTxtInvoiceCreatePost::main(dlgCustAcc.value(), dlgLedgerAcc.value());
else
throw error(strfmt("Either CustAccount or LedgerAccount info is missing."));
}
}

Class:
Which creates the free text invoice
class FreeTxtInvoiceCreatePost
{
}
static void main(CustAccount _custAccount, LedgerAccount _ledgerAccount)
{
CustInvoiceTable custInvoiceTable;
CustInvoiceLine custInvoiceLine;
CustTable custTable;
LedgerTable ledgerTable;
CustPostInvoice custPostInvoice;
LineNum lineNum;
int i;

ttsbegin;
custTable = CustTable::find(_custAccount);
custInvoiceTable.initFromCustTable(custTable);
custInvoiceTable.insert();
ttscommit;

for(i=1; i<=5; i++)
{
ttsbegin;
ledgerTable = LedgerTable::find(_ledgerAccount);
custInvoiceLine.clear();
custInvoiceLine.initValue();
custInvoiceLine.LedgerAccount = ledgerTable.AccountNum;
custInvoiceLine.initFromCustInvoiceTable(custInvoiceTable);
custInvoiceLine.AmountCur = 10.00;
custInvoiceLine.Description = 'FreeTxIv' + int2str(i);
custInvoiceLine.TaxItemGroup = 'full';
custInvoiceLine.ParentRecId = custInvoiceTable.RecId;

lineNum += 1;
custInvoiceLine.LineNum = lineNum;
custInvoiceLine.insert();
ttscommit;
}
}