Kaltura_Client_Exception thrown

Invalid KS "YzUyNDQ0ZGFhOGY0YTE0ODBhZGVhMzhiM2E5NjE4MTJkMjlmMDI2OXwxMDE7OzE0OTM1MTA3ODc7MjsxNDkzNDI0Mzg3LjUwMDE7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"