Try put some more horizontal branch on the upper cage with a safety basking spot distance without creating a hazard for ur cham to get burn by the heat lamp,measures by a accurate digital temperature monitoring devices with the preferably temp range on ur specific type of the cham.
I would suggest taking the leafy plant from the bottom left corner and attaching it the highest horizontal vine you have up in the center as it has been my experience that healthy, happy chameleons usually spend most of their time in the upper one-third to one-half of the enclosure and most often only venture down near the bottom when hunting or when it's time to sleep.