If, at any time, in the judgment of the Secretary of State, the liability policy filed hereunder, is not sufficient for any good cause, he may require the owner of such motor vehicle who filed the same to replace, within fifteen (15) days from the date of notice given, said policy with another good and sufficient liability policy or bond, in accordance with the provisions of this Act. At the time of replacement or at the expiration of the fifteen (15) day period, as the case may be, the Secretary of State shall mark the policy “Cancelled.”
     Upon the cancellation of any liability policy hereunder the liabilities on said policy shall thereupon cease as to any future damage or injury.