Try a walk in. I missed mine once and the security guy wouldn't let me walk in. I lost my actual receipt and when I found it later that day they had closed. Went back the next day and he said I HAD to mail my original receipt and request new appointment date... Hopefully your security dude will be nicer.
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AOS Application sent 12/10-15/16::: Notice of action 12/22/16
Bio letter received 1/15 ::: Bio appointment 1/31::: EAD Arrived 4/4/17 ....Interview: 6/14/17-Approved on Spot