Vw sold me a lemon

I bought a demo 2018 polo from vw Constantia in October with 9000kms on delivery, I drove the car for only 4000kms then two error appeared on the screen: Error : stability control Error : parkpilot

Steering wheel is not aligned and is making a knocking sound when I turn. I took my car for service before time to check the defects, I was told that my car has been in an accident before and that was not disclosed to me, as result of that I will have to pay for repairs from my pocket since it was not a normal wear and tear.

How m I supposed to pay for something that I didn't cause or made a were of when buying the car.

The law says I have the right to take it back for full repair or request a swap or give it back for my refund.