What does he do when you put the tongs and food in front of him? Does he try and back away from them, or does he kind of hunker down. Either way just keep trying, some take a lot longer then others. Everytime you feed try with the tongs first and if nothing after abit just put it in for him. You can try and rub under his bottom lip with it and this will sometimes get reaction even if hes not hungry because it will annoy him. After he eats from them once and sees he wont get hurt by them they usually will catch on. Patience and consistency is the key with tong feeding.