Do you have a pothos or hibiscus in his cage that he might be eating? my veilds would eat almost any plant material they could get their hands on. Sometimes they were too full to load up on insects.
Could be a hunger strike. Also I hear that chameleons eat less during the cooler months, it's not uncommon. I've not experienced this personally though. And you may want to provide a higher basking temp, 80 sounds too low
80 is too low of a basking temperature. most people go from 85-95 depending on age.
also, you'de be surprised how small a roach can be look up dubia roach feeders..your cham will love them. And believe it or not, so will you. theyre sooo easy to maintain. and don't smell!!!