Frustrated William hunt customer

Horrible service i got at William hunt services. I took my chev sonic in . as I have been having problems with it. My engine and abs light comes on and off randomly as I drive. Without changing the performance of the car. The car would still drive normaly no sound no shaking keep up speed as normal. William hunt randburg did there diagnoses and go told it was the spark plugs. they did there repairs paid over 2k. The car did the same thing the same day as I drove back home. Took it to William hunt edenvele for a second opinion got told diagnoses says it's my coil pack and key battery they replaced the coil pack .I got new batteries paid R6700 . 5 minutes later driving home same problem lights on. I'm frustrated, angry and annoyed.