一份對我來說極關重要的信.但是一月多了還沒收到,心急如焚

網站上有朋友說.補件的信丟了.打電話要四十天才能收到.(說法1)
還有的說一個月..(說法2)
還有的說三個月..(說法3)
客服又告訴我幾天後再給我寄一張(說法4)
把我搞得頭都大了,I-485申請一年八個月了.從去年十一月PENDING到今年7月第二次手模.一個月後網上瀏覽得知.On August 10, 2007, we mailed a notice requesting additional evidence and/or information in this case. Please follow the instructions on the notice to submit the evidence and/or information requested. This case will be held in suspense until we either receive the evidence or the opportunity to submit it expires. Once you submit the information and/or evidence requested, you will be notified by mail when a decision is made, or if the office needs something further from you. If you move while this case is pending, call customer service
這個月十號的時候我叫人幫我打了個電話給customer service（因為一個月了還沒有收到）
並把我的地址什麽都跟他們說清楚了。她們回複是再過幾天再寄一張。
可是又一周多了，我真的好無助。不知道怎麽辦才好，好心的朋友們我當如何是好？
律師能追到這封信嗎?
如果知道這封信要我補什麽就好了.我直接做好交上去就行了.
平時信都是直接寄到我家裏的,比如打手模,C9卡補件什麽的.都沒丟過.