I don’t know what to do [Credit] 1. What To Do (Feat. Vahn, 은비(EunBii)) Composed by SIM2, Vahn, 은비(EunBii), HS Lyrics by Vahn, 은비(EunBii) Arranged by SIM2, HS, 유재민 Bass, Piano, Drum, Synth, String by SIM2 Guitar by HS Main Vocal by Vahn, 은비(EunBii) Chorus Vocal by Vahn, 은비(EunBii) Recorded by Vahn, 은비(EunBii) Main Vocal Tune by Vahn, 은비(EunBii) Chorus Vocal Tune by Vahn, 은비(EunBii) Mixed & Mastered by 유재민 Art by neponay