There should be a variance of heat in the cage.
The bottom should be a cool retreat, while a corner in the top is where the chameleon can go to bask. So usually another light is not necessary, if anything giving the chameleon less variance to thermoregulate with.
Heat lamps dont come in 7.0, that is a single digit number, the are usually described as wattage. What is the wattage?
What kind of chameleon is it?
How are you taking temperatures? What kind of thermometer?