Kaltura_Client_Exception thrown

Invalid KS "MzJiZjE1Y2Q1MWNjZTRmNDg4OWI5MWI3YWZhZDljNWJjY2JiYmQ1ZnwxMDE7OzE0OTM1NTI1NDI7MjsxNDkzNDY2MTQyLjY3NTM7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"