Hyundai Boksburg is worse than taking your car to some backyard mechanic

Charged R5700 for a major service on a hyundai i10 1.2 (crazy i know), did not tighten spark plugs so the car had to be taken back after it started showing check engine light and shaking while driving, charged us for 3 hours labour but only worked on the car for 1 hour and gave the car to them with half a tank and got it back with a quarter left (probably went to joburg and back instead of doing effort on the car) would rather take the car to hyundai eastrand next time