Best Mistake 2: The Movie.

Kim Yeon Do (Lee Eun Jae), a studious high school girl, accidentally sparks a relationship with Ji Hyun Ho (Kang Yul), a popular but unserious boy, after posting another boy's picture to deter a persistent suitor. Their budding romance is challenged when Choi Seung Hyun (Lee Jung Joon), a baseball ace, arrives and shows interest in Yeon Do, causing Ji Hyun Ho to become jealous. As their relationship faces this new tension, their classmates also begin to explore romantic connections. Based on a 2016 mobile game, this is a 2021 South Korean movie directed by Lee Yoo Yeon that explores the complexities of young love and high school relationships.