回複：回複：回複：My I-485 pending for security

No one can actually expedite the process of security check, not even US senators. All they can tell you is if FBI already finishes the check or not. "Security check" is indeed a "black hole". A lot petitions get stuck at this stage.

Since your case has been long overdue, you can certainly try to contact the US senators of your residential state, or local congressman. Sometime, it helps.