Wow. Those attorneys! They are always to blame, ha? Where were you looking when you signed that application? The other way?
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I concur with Mr. Tasoff. Bring a corrected copy of the affidavit to the interview. I also agree with Mr. Segal that you do have a duty to review whatever you sign carefully. Fortunately, you did eventually catch the error and are now taking prompt steps to rectify it. Under these circumstances I doubt any damage has been done.