Kaltura_Client_Exception thrown

Invalid KS "YjM4MDMyZGM0YmY0YmNmZDM1Mzk5ZTI4OWYwZTZkMTZmNzYzNjliYnwxMDE7OzE0Njk3MjA1Njc7MjsxNDY5NjM0MTY3LjY1NTk7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"