My ipod nano won't pop up in itunes anymore

Ok try this:

Remove and reinstall iTunes and related software components for Windows 7 and later(Document Type: Document) Nov 3, 2017 In some rare instances, you might need to remove iTunes and related software components before you reinstall iTunes. If you're directed to reinstall iTunes by AppleCare, an article, or an alert dialog, you can do so by following the steps below. Media that you buy from the iTunes Store or songs that you import from CDs are saved in your My Music folder by default. They won't be deleted when you remove iTunes. Although it's highly unlikely that you'll lose any of your iTunes Libraryhttps://support.apple.com/en-us/HT204275

Also if you have this option in settings on the iPod nano try it:

Enable disk use is a setting (checkbox).

Also don't use a dock, connect directly to the USB port on the laptop.

Ok try the suggestions in the article I linked to for the 7th gen, and I will see if I can find information for your model.

If iTunes doesn't recognize your iPhone, iPad, or iPod - Apple Support

Do you have the latest version of iTunes 12.7.1?

Have you tried restarting your computer?

Have you tried rebooting your iPod Nano?

Get help with your iPod nano (7th generation)(Document Type: Document) Jul 14, 2016 Reset your iPod. Press and hold the Sleep/Wake button and Home buttons until you see the Apple logo. If you can't see your iPod in iTunes when it's connected to your computer, try another USB port. Restart the computer that you use with your iPod. Make sure you have the latest version of iTunes. Restore your iPod to factory settings. If you still need help, try the steps for your issue below. https://support.apple.com/en-us/HT203681

Were you able to factory reset your iPod?

Reset your iPod. Press and hold the Sleep/Wake button and Home buttons until you see the Apple logo.

Is there an option in the settings menu on the iPod to reset or factory restore?

I found the instructions for reseting the iPod Nano 2nd gen.

Hold on/off and center+play at the same time for a few seconds until the apple logo appears.

If you plug a USB stick in, does windows recognize that?

What kind of computer are you trying to connect it to?

Is iTunes open when you when you connect it?

How long do you wait before disconnecting it again?