Thank you, but I can't find that Communication section that you are talking about and the only field that says email, is not expandable, you just write the email. I cannot apply your proposal because of that.

Hey,
in odoo, when two existing contacts have the same email address and they are merged, the outgoing mail may not appear because Odoo treats the merged contacts as a single entity. Therefore, if both contacts had separate outgoing emails before the merge, those emails may not be visible after the merge.

To overcome this issue and ensure that the outgoing mail is correctly associated with the merged contact, you can follow these steps:

1. Go to the merged contact's record in Odoo.
2. Click on the "Edit" button to open the contact form.
3. Scroll down to the "Communication" section.
4. Locate the "Email" field and expand it.
5. You should see a list of email addresses associated with the merged contact, including the duplicate email address.
6. Click on the pencil icon next to the duplicate email address.
7. Change the email address slightly, for example, by adding a number or a character at the end.
8. Save the changes to the contact record.

By modifying the duplicate email address slightly, you can ensure that Odoo treats it as a unique email and allows the outgoing mail to be associated with the merged contact. Repeat these steps for any other duplicate email addresses if necessary.

After making these changes, you should be able to send outgoing mail to the merged contact without any issues.