VW the Glen are ******

Bad service at the Glen vw I took my vehicle in for a waar y repair they kept. My vehicle there for over a week and could still not fix it. So they called me tto pick up my vehicle and I noticed that the head light switch on my car is not the one I left my car there with and my vehicle fuel was on empty but they claim that they never drove my car. So tell me how does a car go from half tank to empty. I noticed the switch has a white illumination and mine had red becouse min y car interior lights are red all thy hey cv an tell me is that they never touched the switch but the point is the switch was changed if the dealer does not know then they must tell me who drove my car coz maybe that person will know