I have been waiting i filled 2/7/2018 and I was supposed to receive my refund 2/28 and I received the same letter 3/1/2018 but the letter is not asking me for nothing or to do anything. Told me to wait the 60 days :( so I have been calling and calling and all they can say is hang tight. Yesterday a rep at the IRS told me nothing is wrong that she can see that I just need to hang in there Its crazy.
