As one of the other responders said time is the key and if it has been too long only calling steelseries and hoping they will be able to do something is all I can say. If not you shouldn't have too much trouble.
You should contact steelseries directly, try it with an email or looking for a customer service number on their webpage: www.steelseries.com A receiptwill be asked so you better have it on your hands at the time you make thecall or ask for information.
If your mouse stops working you should go directly to the steelseries website and request service with them. Normally you would request an RMA (Return merchandise authorization) and you would ship the mouse out for inspection. Once the problem is identified typically steelseries will send you another mouse in return for your broken one.