I got my veiled chameleon and he used to be very bright and when I got him he turned very dark and every body told me to wait and I did its been 3 months and he is still very dark.
We need more info from you. Please go to the health clinic and fill out the ask for help form. Also pics of your set up and pics of your chameleon are helpful also. The more information we have the better we can help you!