Kaltura_Client_Exception thrown

Invalid KS "NjFkMDlhNTU2NjBiNGViM2IwYTYwOTFjMDVmNjk2MzBlMzhiYjU3Y3wxMDE7OzE0OTMzMTQ4MjM7MjsxNDkzMjI4NDIzLjA1OTI7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"