Log in to your Student Center. If we have identified an overpayment and request a refund, please mail the check along with a copy of the overpayment request letter we sent you.Clearly state the decision regarding the refund. View options for satisfying overpayment. Submit a Voluntary Refund - A voluntary refund is when an overpayment has been self-identified. I know that you have been frustrated and asking for a refund. In the event that you have received overpayment, please return the funds to Cigna Healthcare SM at: Cigna Healthcare PO Box 188012 Chattanooga, TN 37422.