After you file

I have already sent my tax returns in. The IRS said they wanted to make sure I was myself. They said they where sending a packet to prove myself. I never got it through the mail. And now I filed for my taxes and was asked to prove my identity through a packet in the mail and I never received it. I'm asking now what to do? I guess I needed to take a picture of my photo I.d. or something through a packet I never got. I'm extremely confused.