8老师,您好。我父母去年在广州通过了绿卡面试,要求今年4月份前来美国,但是他们来美国的飞机由于新冠的原因被取消,来不了,请问我应该怎么给他们办理延期,谢谢。
-Read this site for more contact information on phone#, email contact, etc.:
https://china.usembassy-china.org.cn/visas/immigrant-visas/contact-us/
You may email and also call them.