If you are indicating that, at some point, you changed your Apple ID email name, but failed to sign out of iCloud before doing so, then you need to do this:
1. Go back to Manage your Apple ID and sign on with your current Apple ID and password. EDIT the Apple ID back to the old Apple ID email. This is temporary. DO NOT VERIFY IT. Do not change the password: Apple - My Apple ID
2. Go to your iPod and under Settings>iCloud, scroll to the bottom of the screen and Sign Out/Delete the iCloud account. Type in your current Apple ID password when asked.
3. Go back to Manage your Apple ID, sign on with the old ID and current password, and EDIT your Apple ID back to the new ID. (you may have to verify it again).
4. Go back to your device, and sign onto iCloud with your current Apple ID.
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