Here's a few things to check. Folks here can help and let you know if anything is off if you answer these. Typically a happy ball python will spend most/all of the day curled up and hiding, and then maybe roam a bit at night. If she's a brand new snake, though, or in a brand new enclosure, it might just be that she hasn't settled in yet.
What are the temperatures on your hot side and your cool side?
What are you using to heat the enclosure and how is it measured and regulated?
What's your humidity?
What kind of hides are you using?
If you have a picture of your setup that'll help even more.