Hello, My name is ***** ***** will be assisting you today.
You need simply need to log out of the old account name and log in with yout new email address :
If that didn't work, You will have to restore the iPod Touch to a base firmware install, which will erase everything on the iPod :
1-Download Itunes from : https://www.apple.com/itunes/download/
2-Install itunes and plug in your iPod to your pc
3-press and hold the home button and the sleep/wake/power button at the same time for 45 seconds until the Apple logo appears, once that appears you can release the buttons
4-iTunes will give message iTunes has detected an iPod in recivery mode you must restore this iPod to continue
5-click restore if it does not go through click on the iPod in the left hand side of iTunes and click restore
6-restore iPod and now you should have your iPod back.
Additional Information (For ipad/ipod/iphone) : https://www.youtube.com/watch?v=Shrc3FeCJEQ
Hope this help, if you need further help please let me know and i will gladly continue to help