Kaltura_Client_Exception thrown

Invalid KS "Mzg3N2NhNWNmZmEzOTQ2MGNiZjgwOTgwODQzYTNhYTkwZTdiMDI0OXwxMDE7OzE0NzQ5NDIyMDk7MjsxNDc0ODU1ODA5LjkxMDM7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"