computer does not recognize Ipod touch 6th gen

My Ipod touch 6th gen is not recognized. I tried looking for Apple Mobile Support Device in Device Manager, but it does not exist. I have been able to connect in the past, but no longer. I have tried several USB cables. For the new songs that I wanted to sync with iTunes, they show on the Ipod Touch, but I need to be connected to Wifi for them to be played, otherwise they are grayed out. Is there a driver that I need to download? Should I reinstall iTunes?