”A-Side Single by Oh My Girl. Music Video streamed over 10 Million times first 2 days after release and 23 Million first week. Single went straight in on #1 place on Korean Melon, Genie, Bugs, Soribada Charts and #2 on FLO. Surpassed all OST hits and ranked #1 on iChart. Ranked #1 on MelOn Artist Chart (Overall) pushing BTS to 2nd place.” Song is written by Andreas Stone Johansson / Steven J Lee / Laurell Barker / Sebastian Thott.
Check this link for more cool information: https://www.allkpop.com/article/2020/04/oh-my-girl-unbelievable-comeback-conquers-all-charts-joins-bts-on-the-top