Why did Song apologize to Sean?

It's because of the flight delay. According to Netease News Network. Song apologized to Sean for the flight delay, which was caused by the illegal intrusion of a generation of photographers. The behavior of the agent photographer interfered with flight safety, resulting in flight delay. Although neither Song nor Sean has a direct interest, the flight delay has something to do with Sean. Therefore, as Sean's partner, Song needs to apologize to Sean.