Kaltura_Client_Exception thrown

Invalid KS "ZmFhN2VjOGQ5NjgwM2EwY2FjNDFkYWM1MWUzZWFlZGIxMmVlNDBjOHwxMDE7OzE0OTMyMzg1MzU7MjsxNDkzMTUyMTM1Ljg2MDY7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"