Kaltura_Client_Exception thrown

Invalid KS "YjA3OWU1MTU2NzU5OGNlNzc1N2EyZmMwYTk1MWFkMmFiNTUyN2ZmMnwxMDE7OzE0OTMzNzc0ODA7MjsxNDkzMjkxMDgwLjY3ODU7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"