Contact Notes sync is turned off by default. You will need to enable it before you can sync notes. Please do the following to enable Contact Notes sync:

1. Go to your account settings.
2. Click Contact Fields.
3. Search for Notes. 
4. Click the Write and Overwrite boxes in the row.
5. Click SAVE. 
6. Perform a manual sync on the CiraSync home dashboard with the Update Cache box checked or wait for the next scheduled sync pass.