Thanks @Horst Graner | c-3 for the clarification. This is much clearer.
For the first problem "The mail to the users is not the one from ECP", per my understanding, do you mean the actual mail that goes to the user includes more information than the ECP settings? If this is the case, this is the expected behavior. The custom message we set in ECP is ADDED to the notification email to the user that their device is in quarantine, not replace the original notification.
Let's say in ECP I entered the text below:
And this is the notification message sent to the USER:
As we can see, the customize text is prepended to the original notification.
As per the second problem that the content of the mail to the admins are incorrect, I tried to test in my lab by modifying the admin in the list from ECP but cannot reproduce the issue you encountered, the content in the notification message changed accordingly. Given this, please run the command below to verify the admins set for the administrator notification:
Get-ActiveSyncOrganizationSettings | fl AdminMailRecipients
Meanwhile, try reset the admin list using the command below and check the result:
Set-ActiveSyncOrganizationSettings -AdminMailRecipients administrator@contoso.com,mkxxxxxx@contoso.com
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