I have a couple of troubleshooting steps for you to try in order to resolve this issue with your contact syncing on your iPod nano. The first step would be to just try resetting the iPod. An article explaining how to do that can be found here:
And the exact directions for your iPod are found here:
1. Toggle the Hold switch on and off. (Slide it to Hold, then turn it off again.)
2. Press and hold the Menu and Center (Select) buttons simultaneously until the Apple logo appears, about 6 to 8 seconds. You may need to repeat this step.
Tip: If you are having difficulty resetting your iPod, set it on a flat surface. Make sure the finger pressing the Select button is not touching any part of the click wheel. Also make sure that you are pressing the Menu button toward the outside of the click wheel, and not near the center.
If the above steps did not work, try connecting iPod to a power adapter and plug the power adapter into an electrical outlet, or connect iPod to your computer. Make sure the computer is turned on and isn't set to go to sleep. Try resetting the iPod while it is connected to power.
If that doesn't resolve the issue, then you may want to try restoring your iPod to factory settings. More information on this can be found right here:
You may even need to reset the SyncServices folder on your computer if you still have issues with your contact syncing. This article can help you accomplish that task, if necessary:
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