You should contact Marriott Rewards, either by phone or by email, to have the points posted properly. Once, I waited until I had 7 stays that did not post the welcome gift properly at the Tysons Corner Marriott. It took about 20 minutes to get those stays and 3 others at another hotel corrected. The Rewards agent sent a note to the Tysons Corner Marriott to improve their posting of the platinum welcome amenity after making the corrections. At least for this hotel, I have not yet had any more problems with the welcome gift posting properly since that happened.