People Only Mode - Motion Setting

I believe the steam exhaust from our boiler is setting off the motion alert on one of our doorbell cams. I reviewed all of the videos and could see nothing but the steam as it exited the exhaust pipe. The steam is passing across the view about twenty feet away from the doorbell cam. I spoke with a Ring tech person but she could not give me a definitive answer. I wonder if anyone else has had a similar experience ?