Jailbreaking voids the Apple warranty and also means that you will not get any support from Apple, including from this Apple forum. Jailbreaking can't be discussed in this Apple forum.
You can try putting the iPod into DFU mode and see if that will let you restore and remove the jailbreak:
Some jailbreaks cannot be removed and in some cases will permanently disable your iPod. If that happens to you, then you will have to buy a new iPod; Apple will provide no support, warranty or out-of-warranty, for a jailbroken iPod.
You're on your own from here. We can provide no further help with a jailbroken iPod in these forums.