Kaltura_Client_Exception thrown

Invalid KS "NzA4MTM3YTlhNDI0ODQ2OGM1ZDA1YWIxNjQ5MjFjMGVmOGJkMDljZHwxMDE7OzE0OTA4OTUyMDA7MjsxNDkwODA4ODAwLjg3OTc7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"