Seriously there is soemthing wrong here. If you have to hold the =gecko in your hand to stimulate them to eat, its cage is too cold.
You should be keeping them in an area that does not have a drastically different temp than the cage. You want the hot side to be close to 85-90 on the surface of the floor of the cage. It comes from Pakistan, its warm there during the day. get a fecal sample done, sometimes captive produced animals have parasites, especially if it has been in contact with multiple animals (pin worms are easy to spread within a collection).
You shouldn't be giving the gecko more than a few crickets at a time. Never dump more than 6 crickets into a cage (for one animal) at any feeding time, unless you see it eat every insect. Vary the diet a bit. They do not consume one type of insect in the wild, they are foragers, they eat what they can. Are you using any type of supplements. I recommend using herptivite, repcal with D3, mineral indoor vits, and trical calcium powder. Any combo works as long as you use one multi-vit and one calcium.
Check the basics before trying drastically different prey.