Contact the office, or even perhaps the emergency maintenance line to discuss with the maintenance technician on-call. If it is a handicap spot taken by a non-handicap marked vehicle, you could also call the local authorities.
Unfortunately, this is not something that can be dealt with immediately. Get the license plate (or just take a picture of the back of the car so you get the plate and also the make model and color) and contact the office in the morning. Even if that car is NOT in our files at least your complaint is on record if it happens again.
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