No permit, invoice, or claim for refund shall be assigned. A permit may continue to be valid, in case of the death of the original permit holder, for the unexpired term of such permit. In case of death of the applicant or purchaser, refund payment shall be made to his or her spouse, heirs, or estate. Personal representatives of any deceased permit holder may apply for and receive refund payments on purchases made prior to the death of such permit holder or upon purchases made during the remainder of the term of the permit.