Hey! Be More Confident summary:

Gu Ge just returned home to meet the girl that's always on his mind, Bai Yu, who's unable to recognize him due to her suffering from face recognition loss. After a few days of getting along, Gu Ge found that she is no longer as cheerful and lively as before. Why did she lose her light, and what has she experienced over the years? The girl who suffers from prosopagnosia and the boy who sets his mind to heal it. When we were young, it was you who taught me about self-confidence. Now, it's time for me to teach you. Hey! Be more confident. A redemption story is about to unfold.