Kaltura_Client_Exception thrown

Invalid KS "YTI0YzA1MGJkOWVkYTAyMzdiMmNlZmMyNjUxMmZkOWU5NjA0ZjkzOHwxMDE7OzE0OTg2OTcwMzU7MjsxNDk4NjEwNjM1LjIzMDE7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"