Kaltura_Client_Exception thrown

Invalid KS "NGVjMDVkZTBkNDA3ZWY1MWYxNTA5NGUyMjZlOGY3ZjQwMzNiOTM5MXwxMDE7OzE0NzQ5MTkyMjk7MjsxNDc0ODMyODI5LjA4ODk7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"