Kaltura_Client_Exception thrown

Invalid KS "YTRhZjliMzlmZTYwZjY2NjJkNTI0OWFmODFkZmE3OWNjZjFhZjVmYnwxMDE7OzE1MDEwODgwMDI7MjsxNTAxMDAxNjAyLjE4MDE7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"