Any corporation which has paid occupation tax in excess of the proper amount of the occupation tax imposed in sections 21-301 to 21-330 shall be entitled to a refund of such excess payment. Claims for refund shall be filed with the Secretary of State or may be submitted by the Secretary of State based on his or her own investigation. If approved or submitted by the Secretary of State, the claim shall be forwarded to the State Treasurer for payment from the General Fund. The Secretary of State shall not refund any excess occupation tax payment if five years have passed from the date of the excess payment.