Kaltura_Client_Exception thrown

Invalid KS "YjQyZGNlZmI1ZTkxYjc4NjQ0MzhlMTYzNWRhYjdhMTdlMmQwOTZjOHwxMDE7OzE0ODA4NDQ3MDU7MjsxNDgwNzU4MzA1LjI3NDk7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"