Ok I have had this problem a few times were my ball pythons wouldn't make the switch from mice to rats and couldn't find any really helpful posts on the Internet all I kept reading is try asfs or just don't try and wait a month but she still wouldn't eat a rat after months but would take down 3 to 4 mice a week but I was watching a video about scenting pinkies to smell like fish to feed baby rhino rat snakes so that gave me the idea of scenting rats with the shavings from my mouse cage so I got a container and put a layer of shavings from the mouse cage in it and put a rat in their for about 20 minutes then I took him out to try and feed my ball python and within one minute she took it I did that 4 or 5 times and I was able to stop scenting them with the mouse shavings thanks for reading and I hope this helps