ok, first of all your temps are too low. 22-24C night =71-75F, day 27-29C is ok, so heat it more at night it should be around 25-26C. Big swing in temps day/night might force him to sense it is winter time.
next - cover 3 sides of the enclosure.
some frogs have harder time catching moving food, my male is one of those. they want to eat, can't get it easily, get discouraged, stop trying and are scared of tongs. so get a piece of nightcrawler and rub his lips a little, he may or may not eat it at first, but you gotta be persistent, he will get mad at some point, bite it and eat it

but don't to annoy his too much right away, he might get scared. do it every day, at some point he will get tongs=food and will have no problems further on.