Kaltura_Client_Exception thrown

Invalid KS "MDk5MGQyYTgxMzAwMDIwYTRhNjVjYTBkYjFkMTBjZDE1ZjM5MDFmMHwxMDE7OzE0ODc4NDg2MjQ7MjsxNDg3NzYyMjI0Ljg5NzQ7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"