I just found two separate charges for rooms that I had canceled at the Crystal Gateway. I watch my reservations like a hawk so I could not understand how this happened.

Marriott Guest services indeed indicated that I had canceled all my reservations at that property and she got in touch with Marriott Business Services who confirmed that their was a glitch -- at least with respect to my reservations -- and that two of the canceled reservations were not reflected in their system. They are going to rectify the situation for me, and if you have the same problem, contact Marriott.

It would appear that since this happened to me on two separate occasions, that this might be a widespread computer glitch.