Why is one of my budgies so afraid of me?

I have 2 budgies, when I first bought my first one he stood on my hand and shoulders on the first day I got him, I even fed him. He was a couple months old. Now, 3 months later, I bought another one, but shes absolutely terrified of me. When I bring my hand with 5 inches she jumps and screams and runs away. It's been a month, and its still the same. I cant feed her millet when she comes out because she wont get near me, but sometimes I toss it near her and she gets it. She doesent get used to my hand either. Only once, on one day she let me pick her up, i have no idea why. What can I do? I want to hold her like the other one.