I would recamend checking the carb to see if there is a slug of dirt in the carbarater, this could cause a starvation of gas! if this is not the problem i would try checking the gas line to make sure it is not pinched or put into a twist that can cause only a small amount of fuel to get threw...
This might sound gross but you have to take worms and mush them up, the chick can't eat a worm that is not cut up. The bird probably wont eat very well but good luck!