Read this for calling USCIS:
https://gethuman.com/phone-number/US-Citizenship-Immigration-Service-USCIS
另外拿已經蓋過一次延期章的綠卡去蓋章延期需要預約嗎?去年3月辦renew綠卡打指紋時已經蓋過i551章,下月到期。
-You need to make an appointment with the local field office, not ASC . Read this:
https://my.uscis.gov/en/appointment/v2?