As a general rule when an overpayment determination is made a notice of your right to appeal is included in the final determination and there is a time limit to file those appeals. If a potential client were to call my office with this question I would likely refer them to the "unemployment law project" which is a non-profit working in this state to help people with matters such as this. You should be able to google their contact info. If not you can call my office on Tuesday and I will try to get you a number for them. Good luck.