Do you have your Work computer setup to sync the Notebook you are using?
On your work computer, open OneNote and "Right-Click" on the Notebook you want to view on your phone and select the Sync option.
Do the same from your phone and home computer to make sure all of them are syncing correctly. It may be an issue with the password if you have it password protected as well. The sync process won't complete if you don't have the correct password.