So I have an eleven month old beardie who normally loves his greens. His favorites are collards and dandelions. Suddenly, he has decided he doesn't want greens anymore. He will eat his dubias with no problem. The only way to get him to eat his greens is to put pieces in his mouth while he's chewing his bugs.
Try offering some different veges for a bit and see how those go over. They can sometimes get bored with the food offered or just go through picky phases. Sometimes changing up the offerings a bit can help. If eating greens is the norm though he will likely get back into them after a while.