Customer service at Marriott has taken a huge downturn in the five years that I've been an owner. I've just been informed that owners of Marriott Hawaii properties often cannot see their reservations on-line and that the problem has existed for "several months." I was unable to change a reservation that I had previously made because I couldn't access it on-line. By the time I got to the customer support supervisor, the timeslot I wanted was gone. The customer support manager with whom I spoke, Amy, couldn't believe that I thought it unreasonable that the problem had not been fixed. I spent an hour and a half on the phone with absolutely no resolution and am stuck with a week I can't use. In the meantime, Marriott is apparently "working on the problem."