Kaltura_Client_Exception thrown

Invalid KS "YzViMDMyMjE5NzM0NzYxZjI3ZjY2ZWU5M2Y4NDhmNzg4ZmRlNjIzMXwxMDE7OzE0NzU0NDgzMDM7MjsxNDc1MzYxOTAzLjk0O0Fub255bW91cztlZGl0Oio=", Error "-1,INVALID_STR"