I have an ipod nano 3rd generation and it won't unlock

1. Plug the ipod USB cable into the bottom of the iPod Nano.
2. Plug the other end of the iPod USB cable into a free USB port on a Mac or PC computer.
3. Open the iTunes application by clicking on the Dock icon on a Mac or using the Start menu on a PC.
4. Click on the name of your iPod Nano under the "Devices" list in the iTunes window.
5. Click on the "Sync" button to establish a connection between your iPod and the computer.
6. Click on the eject symbol next to your iPod's name after the syncing process has finished.
7. Unplug your iPod Nano. The device will be unlocked and you will be able to access all normal features again.