Any and all mortgage releases and assignments of mortgages which have been recorded in the office of the register of deeds, in any county of the state of Kansas, purporting to cancel and discharge or assign any mortgage, and purporting to be executed by any mortgagee, or his or her agent or attorney, or by any assignee of said mortgagee, or his or her agent or attorney, or by any executor or administrator of any deceased mortgagee or deceased assignee, or purporting to be executed by the heirs or legatees of any deceased mortgagee or deceased assignee, or by any person acting for a corporation, who is either mortgagee or assignee of said mortgage, shall be deemed to be valid, and the lien of such mortgage shall be deemed to be canceled, and released notwithstanding any defects in the execution, acknowledgment, certificate of acknowledgment, recording or certificate of recording of the same: Provided, That this act shall not apply to any release or assignment which has not been recorded in the office of the register of deeds, in the county where the land is situated, at least five (5) years prior to July 1, 1957: Provided further, That this act shall not apply to any mortgage unless the debt secured by such mortgage has been due and payable for at least five (5) years prior to July 1, 1957: Provided, That this amendment shall not revive any rights or actions previously barred.