Hi
These iPods are getting a little on the older side now(that’s one of the things that makes them sooo cool!)
With age batteries degrade and don’t always hold their charge as well as they used to,I have a 6th gen too and one day it died and didn’t charge back up
This issue was caused by a bad battery and I suspect it is probably the same issue in your case
You can fix this by replacing the battery which is a soldering job,it’s not the easiest but not the hardest ether
Here’s a guide in doing it
[link|https://m.youtube.com/watch?v=fO3BUmM_iqY|https://m.youtube.com/watch?v=fO3BUmM_iqY|new_window=true]
Once the battery has been replaced your iPod should be all good to go!
Hopefully this helps
Any questions please ask
Thanks:-)