Kaltura_Client_Exception thrown

Invalid KS "YzAxOTM4ZWIxMzg0OWFlN2JjYzg2MTE1YTU2MjMyMTJjOTU1Yzk5OHwxMDE7OzE0OTgzMjY3ODM7MjsxNDk4MjQwMzgzLjY2Njk7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"