1. some dont like feeding while shedding. Mine do, but some of my friends wont.

2. Are your temps/hides right? If the hides are too big it could be stress. If its not warm/cool enough their feeding could be off. 80-85 one side, 90-95 the other side.

3. How young is the snake? Is the mouse too big? My roomates wouldnt eat the first few weeks he had it. Probably just settling in.

If all else fails try and feed it in its tank. Maybe thats where it feels comfortable and a tub isnt.

Good luck.