diff --git a/mail_tracking/models/mail_thread.py b/mail_tracking/models/mail_thread.py
index c2718cc..cc10100 100644
--- a/mail_tracking/models/mail_thread.py
+++ b/mail_tracking/models/mail_thread.py
@@ -29,17 +29,20 @@ class MailThread(models.AbstractModel):
             ("mail_tracking_ids.state", "in", list(failed_states)),
         ]
 
-    @api.returns("self", lambda value: value.id)
-    def message_post(self, *args, **kwargs):
+    @api.model
+    def _message_route_process(self, message, message_dict, routes):
         """Adds CC recipient to the message.
 
         Because Odoo implementation avoid store 'from, to, cc' recipients we
         ensure that this information its written into the mail.message record.
         """
-        kwargs.update(
-            {"email_cc": kwargs.get("cc", False), "email_to": kwargs.get("to", False)}
+        message_dict.update(
+            {
+                "email_cc": message_dict.get("cc", False),
+                "email_to": message_dict.get("to", False),
+            }
         )
-        return super().message_post(*args, **kwargs)
+        return super()._message_route_process(message, message_dict, routes)
 
     def _message_get_suggested_recipients(self):
         """Adds email 'extra' recipients as suggested recipients.
diff --git a/mail_tracking/tests/test_mail_tracking.py b/mail_tracking/tests/test_mail_tracking.py
index 2411e8a..3ebda76 100644
--- a/mail_tracking/tests/test_mail_tracking.py
+++ b/mail_tracking/tests/test_mail_tracking.py
@@ -182,7 +182,7 @@ class TestMailTracking(TransactionCase):
         # pylint: disable=C8107
         message = self.recipient.with_user(sender_user).message_post(
             body="<p>This is a test message</p>",
-            cc="Dominique Pinon <unnamed@test.com>, sender@example.com",
+            email_cc="Dominique Pinon <unnamed@test.com>, sender@example.com",
         )
         # suggested recipients
         recipients = self.recipient._message_get_suggested_recipients()
@@ -235,7 +235,7 @@ class TestMailTracking(TransactionCase):
         # pylint: disable=C8107
         message = self.recipient.with_user(sender_user).message_post(
             body="<p>This is a test message</p>",
-            to="Dominique Pinon <support+unnamed@test.com>, sender@example.com",
+            email_to="Dominique Pinon <support+unnamed@test.com>, sender@example.com",
         )
         # suggested recipients
         recipients = self.recipient._message_get_suggested_recipients()