Filed my taxes like I do every year

So I filled my taxes the same way I do every year with TT. Followed all the rules did it step by step. I get told that I’m going to get a federal refund of 1520 I think this great. I can maybe do a down payment on a car this will be amazing woke up yesterday to see that it was changed by the irs to 120. I know that the irs can change things or if it wasn’t right but I don’t know what I could have done wrong. Nothing besides jobs has changed in my life. This entire process has been super defeating I have called and talk to all I could talk to nothing makes sense