Kaltura_Client_Exception thrown

Invalid KS "YWI0YzViYWUzZDZhZDYxNGJhMjc4YzZiYWM0MjE2NWY5M2NmMDc5ZXwxMDE7OzE0NzUxMTQ5Mjk7MjsxNDc1MDI4NTI5LjY0NjM7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"