It may also have something to do with the way you are thawing and presenting the F/T. After thawing, I use a blow dryer to heat the prey up for a minute or 2 and I blow the air into the enclosure to pre-scent and let the snake know a meal is coming. Grab the prey with feed tongs by the skin on the back of the neck and wiggle it around about 3 inches in front of the snake so it looks more natural, and let the snake come to it. You also might need to try a live hopper mouse or rat pup next time. Something that weighs 10%-15% of your snakes weight...