Thanks for choosing Notezilla .
Master password is different from the sync account password. Master password is used to lock and encrypt a single sticky note.
To change the sync account password, right click on Notezilla icon (next to the clock) in the taskbar and select Sync from the menu and click on Account settings button. There you will find a link "Forgot password". Use that to reset the password.
Alternatively you can also go to this link to reset the password: https://www.notezilla.net/Account/ForgotPassword