Strange, I have a similar problem right now as well.

I'll put the container on the screen of the tank, stick my hand in the container and get the rat to run a few laps around it's container (generally the scratching noise is enough to bring Ruth out of her hide and cocked back at the container).

Last feeding day did this, all went as it usually did. Only she hesitated a moment, went for the rat and missed, then didn't show interest at all after that.

Tried again 20 minutes later, again 20 minutes later, again 20 minutes later. She showed interest, but didn't go for it. Cocked back, starting hitting it with the tongue, then pulled back into her hide very fast. Took the rat back to the breeder and said I'd be back in five days.

Now for the past 4 days she's been up hunting every night. Go figure.