64(1)The officer-in-charge shall on the first day of each month, or quarterly, send a written notice to the person liable for the payment of the maintenance of any patient, giving the date of the patient’s admission to the psychiatric facility and the amount that is due and owing for his maintenance, as provided by the regulations, and in that notice a demand shall be made by the officer-in-charge upon the person liable for payment of maintenance for such sum as is due and owing, and the sum shall be paid forthwith on the demand.