It could be a picky eater. Or something may have stressed him/her which will also cause them to not eat. I would try different food items incase the problem is just a picky eater. Try wax worms and meal worms. These are by no means good for a staple diet mostly used as treats. Also you could try a red wiggler again. You can offer food before the frog emerges from his/her hole. Just drop the wiggler or other food item in font of the frog. Break the legs off crickets before offering them to your frog to make them easier to catch. If you are worried about illness there is an article on the forum for frog first aid which lists diseases and symptoms of the diseases along with at home treatment recommendations. If your frog starts losing weight rapidly and still doesn't eat you may have to consult a vet.