You definitely need work on your tank layout and husbandry issues. Tank looks really bare. And it's way too big.
For starters, your gecko looks way too thin and underfed. Aside from proper moisture, if they're not healthy, they won't shed properly. Do NOT feed your bugs the bug food that is sold in pet stores. Most of it is garbage. Gut load the bugs with an assortment of apple, carrot, blackberries, kale, collard green, papaya, sweet potato, and green beans, then dust the bugs with Zoo Med's ReptiCalcium (w/D3) and Reptivite, and feed it to the gecko the next day. Don't forget the dusting or your gecko will end up with MBD. You need to fatten the poor thing up. He's looking anorexic.
Your gecko is probably not eating right because of his tank temps. You have a cold-blooded animal. His health and life depends on you keeping his temps perfect. Cold will hurt him. Get his temps fixed ASAP. Buy a point and click thermometer, and check the temps on the floor of the tank. You should have an Under Tank Heater pad (UTH), and you'll need a thermostat as well to maintain the tank floor temp.
Your tank floor should be 33.3° C under the warm and moist hides. Your gecko needs this floor temp to help him digest food properly lying on his belly on the floor.
Also, are you handling them too much? They stress and won't eat when over-handled. Leave them alone for now, other than to do daily tank maintenance, moisten the moist hide once a day, and offer them food. If they are juveniles, you can offer them food every day. Meal worms are measly food, IMHO. I never feed them to my gecko anymore. Try crickets and dubia roaches, they can hold more fruit and veggies in their gut, and will be way more nutritious for your gecko.
Let my tank layout inspire you...warm hide (left), moist hide (middle)...both these hides have the UTH under the tank warming them up. Cool hide (right, UTH shouldn't come anywhere near this hide). If your home is cool, and the ambient tank temp is cool (the air), you will need something to warm it up. You can do this with a dome light, a dimmer (to adjust the temp), and a timer. I have one sitting on my lid here (right side).
Good luck and always come back to ask questions when in doubt.
This forum has saved alot of geckos lives.
