I am reasonably new to bonsai trees getting my tree at the start of 2020. Every winter I have the same problem with my tree's leaves falling off. This year, just like last all his leaves have almost fallen off. I don't think it's normal for him and I don't know what kind of bonsai he is. The bonsai is normally on my windowsill but in the winter he tends not to like it so I move him around the house, he's been away from the window, on the porch, and in the office but it doesn't make a difference. I think maybe I'm watering him too much but at the moment he has almost no leaves so I think I need to revive him. Hope someone can help so this doesn't happen next winter.