HRN is a wholesaler of hotel rooms. A wholesaler gets a greatly reduced rate, and marks it up (usually to a price that's less than what the hotel's selling for) and pockets the difference.
It is common in the hotel industry for wholesalers to have a 72, 48 or even 24 hour cutoff for giving names to a hotel. If you book your room through a wholesaler, you are supposed to take their word for it that you have a reservation, and deal with them if there is a problem. If a hotel works with a wholesaler, there's probably staff that do nothing but process rooming lists and input actual reservations as they come into the hotel. Hotels need wholesalers for marketing and for filling rooms . . . I would worry if they didn't have your name the day before or the day of check-in. Wholesalers fill dozens, if not hundreds, of rooms a night at the place I work.