A good thump to the head of your prey item wouldnt be a bad idea. I have one female that is like 8 years old and she has never fully coiled properly. Since she was a baby she never did it. I thump her rats for her. I know i know some people are gonna say thats inhumane whatever but the rat is food and she needs to eat. But for sure a trip to the vet to get it fixed is in order. Snakes can hold an infection for a while and the longer it sits in the harder it is to fix.