VW Rhodesfield

I took my car to VW Rhodesfield to do 15 point check with them, after they checked they told me it was gear stick that had a problem.Now the car is not starting and it was fine up until I took it to VW for this overall mechanic check.I switched batteries and put a new battery to check maybe its a battery problem.Still the car is not starting and this problem began after taking it to VW. Since Im a woman and Idon't know anything about cars they are taking advantage of me since you are vulnerable