I called to correct a mistake they made for my application. I did call several days ago but I don't think I get the answer clearly. But that man kept asking me why I called again and what the previous representative told me about it. Anyway, he is really not nice.
But in this website, people are always talking about the story, like calling uscis several times in one day just trying to get information of name check. I think such things really mislead me a lot.