diff --git a/addons/l10n_it_edi_sdicoop/models/account_edi_format.py b/addons/l10n_it_edi_sdicoop/models/account_edi_format.py
index dea4c4672cd..f6ed849d479 100644
--- a/addons/l10n_it_edi_sdicoop/models/account_edi_format.py
+++ b/addons/l10n_it_edi_sdicoop/models/account_edi_format.py
@@ -237,9 +237,22 @@ class AccountEdiFormat(models.Model):
                 else:
                     to_return[invoice] = {'attachment': invoice.l10n_it_edi_attachment_id, 'success': True}
             elif state == 'notificaScarto':
-                errors = [element.find('Descrizione').text for element in response_tree.xpath('//Errore')]
-                to_return[invoice] = {'error': self._format_error_message(_('The invoice has been refused by the Exchange System'), errors), 'blocking_level': 'error'}
-                invoice.l10n_it_edi_transaction = False
+                elements = response_tree.xpath('//Errore')
+                error_codes = [element.find('Codice').text for element in elements]
+                errors = [element.find('Descrizione').text for element in elements]
+                # Duplicated invoice
+                if '00404' in error_codes:
+                    idx = error_codes.index('00404')
+                    invoice.message_post(body=_(
+                        'This invoice number had already been submitted to the SdI, so it is'
+                        ' set as Sent. Please verify that the system is correctly configured,'
+                        ' because the correct flow does not need to send the same invoice'
+                        ' twice for any reason.\n'
+                        ' Original message from the SDI: %s', errors[idx]))
+                    to_return[invoice] = {'attachment': invoice.l10n_it_edi_attachment_id, 'success': True}
+                else:
+                    to_return[invoice] = {'error': self._format_error_message(_('The invoice has been refused by the Exchange System'), errors), 'blocking_level': 'error'}
+                    invoice.l10n_it_edi_transaction = False
             elif state == 'notificaMancataConsegna':
                 if invoice._is_commercial_partner_pa():
                     to_return[invoice] = {'error': _(