Kaltura_Client_Exception thrown

Invalid KS "NjExYzM5NWRlMzkxMTM4NWU5MjA2YzFlZDlhNzQ5NjAyZmY0Y2Y0MXwxMDE7OzE0NzUxNTg4Nzc7MjsxNDc1MDcyNDc3LjM3NzY7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"