Song Han Gyeom, formerly known as A-Day, is a member of Spire Entertainment's boy group Omega X debuted on June 30, 2021 and a former member of the boy group Seven O'Clock.

He participated in JTBC’s survival show "Mixnine". Song was announced ranked 6 for the Male Team and was later announced the winner and part of the debut group.

In October 2022, a video of the CEO of OMEGA X's label abusing him and his group members came to light. After more videos and evidence were revealed, the members stepped forward with the intention to file a lawsuit against their company to cancel the exclusive contracts and to file for the trademark of their group name. In January 2023, OMEGA X won the lawsuit and officially ended their contract with Spire Entertainment.

On May 8, 2023 OMEGA X took to Instagram to share the news that they came to terms with SPIRE Entertainment after they mutually agreed to end their exclusive contract as well as all other disputes.

On July 3, 2023 it was announced that OMEGA X has signed with IPQ Entertainment.