Existing, saved manual invoices and credit notes, which are yet to be closed, can be edited. By editing an invoice/credit note, you can change the following details of the invoice/credit note:
invoice/credit note date
invoice type/credit note type account group
invoice/credit note terms
billing contact person
invoice message
credit note reason.
You can also edit the attributes of any invoice/credit items on an invoice/credit note, add additional invoice/credit items or delete any existing invoice/credit items. 
Note:
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If the invoice/credit note date, invoice type/credit note type account group or the invoice/credit note terms are changed on an existing invoice/credit note, any existing invoice items or credit items on the invoice/credit note will be deleted and you will be required to add new invoice/credit items. |
Timesheet based invoices/credit notes created via the invoice batch process are automatically flagged as closed and therefore cannot be edited. If an adjustment needs to be made to an automatically created invoice or credit note, the corresponding timesheet(s) need to be adjusted, thereby triggering the generation of credit notes.