Hi, I sent my N400 application and my wife's N4 application together thru UPS on Sep 15th 2009. I got the confirmation thru UPS tracking number that they delivered the application at 1820 E Skyharbor Circle S, Phoenix, AZ on Sep 18th 2009. But so far I did not get any receipt from USCIS and the checks are also not encashed. It is now one month passed. I tried to call customer service number, but could not able to reach any person. Can some one advise, how can I track my application ? Thanks, Srini