You never tell anyone about what actually happened back then. the incident gave a big effect on your left ear. Your left ear slowly started to lost its ability.

He noticed that you started to train yourself without using the left ears. You only used a earphone on the right side and you always turn into your right side whenever your classmates talked to you.

Gabriel is now talking with you but you couldn't hear it and he woried a little. Then he tap your shoulder to get your attention.