I stay at the same hotel every other month (for a week) and arrive late, after 10pm, I call in the day before and they block or save me my favorite room (or let me know what is available). They told me once I check in on line, they can not change, move or re-assign the room. Maybe try calling in the day before (call hotel directly and do not press anything, just wait till the actual hotel answers). Ask that they assign you a room. Hope that helps.