Why would my OPT get denied is hard to believe Does anyone know the reasons?

In summary, where I stand is that I submitted my OPT application on March 5th through e-filing. Following the submission, I called USCIS several times to ask whether I had to get my biometrics taken and the customer service representatives all said no.

I did not hear back from USCIS until mid-May when I received a bundle of letters that had been returned to the sender (USCIS) for no disclosed reason, but I noticed that in several of the letters they had printed the incorrect zip code. I also called them several times to double-check that they had the correct address and every time they read the correct address back to me. The first letter was a biometrics appointment for March 27th and the second letter dated April 3rd was for a change in my biometrics appointment given the fact that the first letter bounced back. These letters were not received until May 16th at which point my OPT application had been denied because of the lack of biometrics (which I did not know I had to take since I had not received the letters).

In addition, my I-20 had already expired at this point since I graduated on May 15th, 2013 and can no longer obtain an I-20 OPT recommendation from my university because of this. USCIS told me that they have now sent a denial notice stating the options I have to appeal the decision, but the latter bounced back on June 5th and they have sent it again.

hello...............................................