Can a hotel cancel my reservation and not tell me until I'm there to check in?

I arrived at a hotel in London yesterday and was immediately told that someone had cancelled my reservation. Apparantly someone phoned 12 days ago and cancelled it according to the receptionist.None of us had cancelled the booking. Funny how he remembered this cancellation without checking my booking ref or details though. He had a piece of paper ready with my booking cancelled. Just sat there in front of him. He couldn't care less about it and was extremely aggressive. We checked with other hotels in the hope of finding a room for the night and apparantly he is well known for double booking rooms on purpose especially when he can get more money for the room. Does anyone know if there is somewhere I can report this hotel? Thanks