There is a feature on the iPhone that links together duplicate contacts. If your duplicate contacts are linked together, you will not see the notes section in the initial contact information on the contact card in MoxiWorks - it will be in a different section of the contact. If you scroll to the bottom of the contact you will see a section called "Linked Contacts". If you click on "Exchange" in that section you will be able to see your notes from MoxiWorks.