Kaltura_Client_Exception thrown

Invalid KS "NTFjYTcwYjg1MGU1MTI3MTI5MDViZjIxMjBkZjYyYWM3ZWQ1YTMxZHwxMDE7OzE0OTU5ODE1NjI7MjsxNDk1ODk1MTYyLjM0MzE7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"