I have a similar problem. I got my new Spider female (8 months old) 2 weeks ago from a breeder and he said she was eating small live rats every week, however, she has not eaten a week before the delivery to ensure no digestion problems occur during the transport. I set her up in her enclosure and let her without touching, feeding, etc. for about 6 days. After that I tried feeding f/t as I could not get a live rat. She did not take it, she did not even notice it, smell it, go near it. I decided to give her another week to settle down and this time I bought a live small rat, (the size she was used to eating before). I put it in her tank and again, she did not care about the rat, this time she seemed afraid of it.

When I got her she was 300 grams, after 2 weeks she is now 290 grams.

My set up: two hides, water bowl, cool side temp 25-27°C, ambient temp 28-29°C, hot side up to 32°C, humidity 50-57% depends also on the weather.
Her behavior: during the day resting in the warm hide or on the branch hidden in the artificial plant; during the night she is very active (trying to find a way out???)

I already own a ball python and I know that they need a time to settle down, however, my first ball python never refused a food for me, not even when I got him.

Any advice from you guys?