Adult Refusing to eat and pooping on prey

Hello!

I have had a female corn snake for about six years now. She has never had any problems eating until a couple months ago. She has stopped eating, but will still strike at her prey at first. She will act interested, sometimes attempt to eat, then defecate on her mouse and act terrified of it. We recently lost a baby hognose to the same exact situation, except she wouldn't strike at the food at all. The corn snake stopped eating shortly after the hognose. Could something be wrong with the mice, or my care? I try to keep proper temperature gradients, always fresh water, hides, etc. Any advice is greatly appreciated.