Sounds to me like the frog is frustrated or impaired. Does it have full use of all of it's limbs? Have you watched the videos we so painstakingly put together for folks having issues feeding the frogs? You may have to put more effort into teasing the frog with the worms to get him to eat.
Honestly, when we do have a problem with getting a frog to eat it is usually due to either stress or illness. Post some pictures so we can try to help more if possible.