You on TRT or something? Losing fat and putting on muscle don't go hand and hand. You lose fat with muscle with calorie deficit and try to retain as much muscle as possible, you calorie surplus when you lost the fat to put on muscle.
I think everyone should go on TRT personally. It's healthier for you. You feel amazingly confident on testosterone. Like you can handle any problem that comes your way. It's a good feeling.
You can gain muscle and lose fat via noob gains which I assume he was in that noob gain state