Kaltura_Client_Exception thrown

Invalid KS "NmNhZmE2MjczMmM5MmVmMmVmZjFhMGY1NTY3NTYwN2QyNWIyNWZkMXwxMDE7OzE0OTMzNDM0NDI7MjsxNDkzMjU3MDQyLjkzMzI7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"