Kaltura_Client_Exception thrown

Invalid KS "NWNhMGZlYjU2ZDJjODUzNDdmYTM1NmEzMmY0NWI0MzUzMmIwNWI3MHwxMDE7OzE0NzUzNzQyMjI7MjsxNDc1Mjg3ODIyLjk5MTg7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"