Kaltura_Client_Exception thrown

Invalid KS "MDQ1MWQzNDAwNmEzOTgwZmMwMzA4ZGJiOTUwZGIyNjcyYTM2NjBlY3wxMDE7OzE0NzQ4NTcyNjk7MjsxNDc0NzcwODY5LjE5ODk7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"