Shell responsible for car theft

On Saturday I took my car to shell garage woodburn pmb, my regular car wash to have it cleaned, at the time when I had to pick up my car after the wash the supervisors at the car wash says my car has already been picked up by a 'black tall man' who claimed to be my friend and he handed him the keys because he was black and thought I knew him, and that is how I lost my car, everything is on cctv footage but the garage doesn't want to release the footage or take responsibility for their negligence