Maz handing Chewie the medal at the end of ROS doesn’t contradict with giving him a medal in ANH:R. He wasn’t being presented with his own medal in ROS. Maz was giving him Han’s medal, that Leia had been keeping. It was a memento of the friends he had lost and it was being passed down to him. It was an inheritance, not a prize.
Totally new way of looking at that. I like it!