Hey, I got a few senegals and I had same problems. The biggest things to remember is if you have more than 1 that they are seperated and they cannot see eachother in anymeans. Also check the lighting and make sure you got good bulb, I reccomend " reptisun 5.0+ and you should spike the metabolizm and also make sure they have peace around there cages.. Too much of anything can affect the way they eat. Make sure you got all the temp's and light cycles and water and food. Also, some chameleons like a challenge and will sometimes get bored with it and wont eat. Due to the fact he is new to you I wouldnt assume that he is suffering from this.