Has he eaten anything since you got him? What was he eating BEFORE you got him? I would suggest offering a live prey item--whatever he's used to eating. Once he's back on feed, he may be more interested in the one you offer.
You need to make sure his strike is actually an attempt to eat, and not just a defensive 'leave me alone' move. Warming the ft item up to at least 100F will help--don't give it time to cool down before you offer it. (Never microwave them, trust us).