If you are using Fleet Manager Version 3.2.20110.1 or later, right click on the invoice from Accounting > Customer Invoices
Click 'De-Select as EDI Invoice' then when you are ready to send it right click on it again and select 'Re-Send Invoice" with one of the available options. EDI users in this version or later will now be able to re-send invoices as ‘Balance Due’, ‘Correction’, ‘Past Due’ or ‘Rebilling’ using the same invoice number. Users will also have the option to re-send an EDI invoice with a new invoice number
If you are using a Fleet Manager Version prior to 3.2.20110.1 there are 2 options.
Option 1 is to go to Accounting > Customer Invoices > highlight selected invoice > De-Select as EDI Invoice, make your changes, then highlight the invoice again and 'Set as EDI Invoice' -- this will resend the EDI invoice with the same Invoice Number previously used.
Option 2 is if you would like to resend the EDI invoice with a new invoice number that is sent to the carrier, then edit the invoice, right click on the Invoice and “Re-Send EDI Invoice”. The invoice number will now have a "_2" appended after the Invoice number so that it will send a new number via EDI. You should only use that option if you cannot send the same invoice number again due to EDI restrictions of their EDI system.