Why does my mantis have cloudy eyes and it wont move and it wont eat?

one day my mantis is fine and its healthy and it goes through a molting process and everything moltied but its left leg but it still huts and eats and a few weeks later it dosent move, its eyes get cloudy on the edges, it wont move its tail is down and i cant do anything about it because i dont know whats wrong with it and i have looked it up on the web but i still cant find anything can somebody help me :'(