Complete the contact form page and attach a file for ONE of the following proofs of payment for each payment. Click here to search for any overpayments on your PIN.Do I need to fill out an application with the Cook County Treasurer's Office to receive a refund? No. You are all set. Com, Treasurer Maria Pappas said today. This tool identifies duplicate tax payments or overpayments for which a refund may be obtainable.