Kaltura_Client_Exception thrown

Invalid KS "MjlhMWM0MTc3MTgxMWEzZWRkZmNjYTkzYTJiNDljMmVjY2E5NTU5ZHwxMDE7OzE0OTg1NjA5NzM7MjsxNDk4NDc0NTczLjc5NjI7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"