You're dealing with a double whammy of sorts here...I dealt with a similar situation with a 100% het albino girl I bought that came in around 900 grams.

First of all, shipping a ball python to a new place with new sights, smells, sounds, keeper routines, etc, is stressfull enough for a ball python to lose interest in feeding while they settle in.

Second, those snakes are entering the "terrible teens" where they aren't babies anymore but aren't quite adults either...a LOT of people observe that ball pythons get flaky with feeding around this time...not all the time...but enough that it's worth mentioning that it is a possibility. I find that I can get hatchlings up to 1000 grams in a year, but at that point, they start slowing down and it isn't until they reach around 1500 grams that they start slamming food again.

Just give them some time, be patient, go easy on the handling sessions, make sure they have secure hides, and just don't mess with them too much. They'll come around eventually.

Hope that helps.