Kaltura_Client_Exception thrown

Invalid KS "MjU1Yzg0MzVhMmZiM2QyZjlhZWFhZmIzNmZhNWYxZDkzNzFjZmFjY3wxMDE7OzE0NzQ5OTgwNTU7MjsxNDc0OTExNjU1LjMyMDI7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"