Hi there.
I suppose it’s ‘nice’ to know when your guest is coming in, but I’m feeling on the guest’s side here.
He told you a window when he would arrive. If I were the guest I would tell you the flight number or maybe I’d ask why you need to know more beyond the arrival window.
So, yes, I think you acted unreasonably. I would not have cancelled. When the guest said I didn’t need the information I might have written 'Of course, I was just trying to get a more accurate arrival time so I could . . . "