Kaltura_Client_Exception thrown

Invalid KS "YTAyZGRlZjhkNjE5ZGFmNTg5OWE5MTcxZjZiMDE3NWQ2OWYyMzYxYnwxMDE7OzE0OTU5Mzk1MTY7MjsxNDk1ODUzMTE2LjA0NDE7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"