You are well within the warranty period so you could contact SanDisk–use the phone or live chat, email is slow. .
http://www.sandisk.com/about-sandisk/contact-us/
Or if, for some reason, you don’t want to do that, it could be the cord. Charging and data are separate connections, so a defective cord could be the problem.
The mini-USB connector is standard–do you have a camera or phone that has a similar cord for you to try? Or you can buy a generic replacement online for a few bucks.
