Kaltura_Client_Exception thrown

Invalid KS "YWViZGJlN2FmOTdhY2VmMjU2MDZiY2Y5NDdjMDI0MGQ1MGFjNGJjNnwxMDE7OzE0OTA2MTI4MDQ7MjsxNDkwNTI2NDA0LjcxOTM7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"