USCIS Letter

I opened the mail today and had a letter from USCIS. At first I'm jumping up and down because I could tell by the size that my documents weren't sent back again, but upon opening it, I found a letter saying that my application wasn't complete because I had not included a copy of our driver's licenses. The crazy thing is that it is not in the list of needed items per the directions? I think they are just testing my patience. No, as adoptive parents will soon learn, each state is different, as well as the sub-offices in each state.