It takes them time to build confidence.
Solana, my Scaleless Sunglow Motley Red-Factor Corn snake was 8G when I got her. Only 2 months old.
She would devour pinkies at that size, but only if I put in front of her hide and walked away.
Now, and soon after we got her - maybe 5 feedings in - she started grabbing the food off the tongs. She's about 90G now, almost 1 year old, and she begs for food, just like her brother (Hypo-Lavender Adult Male) corn snake.
Give her some time, but also, don't be afraid to leave a f/t food item in there for a bit and leave her alone to see if she eats.