I have had this at the top of 'My Trips' on Marriott's website for about 3 weeks:
'Unfortunately there's an issue displaying some of your reservations. Please check back later. We apologise for any inconvenience.'
The only thing I can suggest is you contact the hotel in future if you can and confirm they've got your reservation. You shouldn't have to do it I know but Marriott's just not reliable at the moment and I dread to think what their IT department is going to do come January and the merger proper.
CLE guy, that's a bit harsh...