"Reply to" Option not show from Teacher Login.
Dear Support Team,
The Reply To option will only show for users who have permission to send from either their personal email or the organization email. This is generally administrators or other users who have the New Message_fromSchool permission in User Admin > Manage Permissions. This exists as a specific permission so that you can control who is able to email on behalf of the whole school, otherwise the Reply To will default to the email of the user sending the message.
Hope this helps!