My steps are from another person in my house

Hi,

I just purchased a Series 9 watch. My wife and kids who live with me, all have Apple watches. I woke up this morning and my watch said between Midnight and 6:00 AM, I did 4300 steps. No that was my son the nurse working the night shift. I was sleeping. My wife also has her fitness data sometimes combined with our other son's data. Is there a way to correct this issue? My son has the fancy Ultra II. If my watch is paired with my iPhone how does this happen?