I think there are problems with your cricket care , can you tell us how you look after them , and what you keep them in, and what you feed them ?
You will need to have a few colonies so you will aways have roaches the right size to use.Probably more bother than it's worth for JUST ONE lizard.
Similarly you don't have the scale to gain much by buying large numbers of bugs by mailorder (in bulk) since you only have one beardie to feed.
You could try phoenix worms as an alternative staple feeder.
re crickets
I take it you are buying your bugs in small qualities from a pet shop, I'd ask them what day they take delivery of their bulk bug supply (each week) and schedule your purchases so you are there within a few hours of the delivery and perhaps even call them that day and ask they set aside a bunch of freshly delivered bugs (in tubs) for you and keep them behind the counter for when you arrive ( it's likely they'll be happy to do this for a good regular customer - so get to know the shop staff).
Lot of pet shops will keep even disgusting tubs of bugs on the shelves in the hope a buyer will take them without checking them before buying and lots will not even feed the bugs.
Then when you arrive visually inspect the tubs (if you see dead bugs in a tub - don't buy it).
When you get you "fresh" bugs home , replace the food in the tub (ie replace the slice of potato or apple or carrot with a fresh cut chunk of carrot - this will supply food and water to the bugs).
I feed my crickets repcal adult beardie pellets (about 8 pellets per tub of 80 medium crickets).
Next , if it's hot , check your crickets each other day, replace carrot chunk if it's starting to feel slimmy (will make the bugs sick) , remove any dead or sick bugs (they go outside for the birds, wild frogs and lizards and the ants), top up the pellets if needed (if the pellets go "fluffy" that's OK).
In cooler weather - OK to let the checks be every 3rd or 4th day, keep the bugs about 24 - 25 degCelsius and in a well ventilated but dark place.
About 2 days prior to using a tub of bugs, put some washed green leafy salad stuff in ( I use either buk or puk choi , the green leafty bit ) , this will help fill the bugs guts with a calcium rich food.
Also save some of the empty bug tubs so you have a stock of these on hand - clean them thoroughly and if a tub with bugs in it gets to nasty, remove the surviving bugs and place them in a clean reused tub .... this can be an issue especially in hot weather .... I've had some really maggoty tubs on occasion in summer.