美签DS-160出现Application Error怎么办？

已经缴费并预约了下周四面签，，昨天下午打印DS-160的confirmation page，爸妈的打出来了，轮到打我的时候，最后出现Application Error，An unexpected error has occurred while processing your previous request. The error has been reported to the site administrator; no further action is required. To retrieve your DS-160 application, please enter your Application ID.
retrieve了也是出现这个提示页面，这是怎么回事呢？求教。