You are in luck... Storeria Dekayi are a specialty.
3 days is nothing, they sometimes take a while to settle in.
The young female I have right now refused food for weeks, then suddenly decided to take worms off the tongs with vigor.
I would like to see a picture of your snake's home.
Dekayi are a very cool weather snake, you will not want to heat the cage very much, they like it around 60 degrees (F), humid and lots of places to hide.
Just make sure you have a shallow water bowl that is easy for the snake to drink from.