Kaltura_Client_Exception thrown

Invalid KS "NGU4ODRiOTJiMDk5MjY1OWYyNGQ5ZmVkYzQ3ZThjODI2ZDdmMmY4MHwxMDE7OzE0NzU0MjkxMTI7MjsxNDc1MzQyNzEyLjg1NTc7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"