I think your chicken is molting. It happens. I've read that it doesn't happen until after they are a year old, but I've had some molt much earlier than that.
Is it acting ill in any way? Are the other chicken's picking at it? If not, it's probably just a mlt and nothing to worry about. Those feathers with the waxy coating are the new feathers coming in to replace the lost feathers. All of your mature chickens will likely molt once a year. Some will lose a bunch of feathers at once and look like your hen, and some will lose feathers more slowly and you might not even even notice them looking much different when they molt.