Forget what the car said, what paperwork did you have describing the car? Its becoiming increasingly well known that Tesla change the spec, its increasingly well known that the update can be late to be reflected in the car, its what the paperwork says describing the car that might give the clue to what you're getting. If you got nothing other than "Tesla Model S, sold as seen" then I can understand your frustration it was "seen with FSD", if the dsscription is "Tesla Model S, clean title. 34k miles, registered 5 March 2019, Midnight Silver, Black premium interior, sunroof, autopilot, etc..." then you're being told what your getting and with respect you'd need to understand that as a professional dealer, however frustrating tesla is.This vehicle had FSD enabled when I previewed the car. I sat in the car and verified it. After the sale, Tesla reverted it back to standard AP.