Kaltura_Client_Exception thrown

Invalid KS "MzE2YTZhYzI1MzQ5MjdjZGNlYWQ3NjM2OTNiYTQ2NDgyMGQ4ZGRhMnwxMDE7OzE0ODUzNzk5NjI7MjsxNDg1MjkzNTYyLjU2NDM7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"