MERCEDES GLC 43 AMG COUPE STEERING PROBLEMS

I own a Mercedes GLC 250d Coupe and a Mercedes GLC 43 AMG Coupe... what a disaster. The AMG was delivery in April 2017 and has had a serious front end/steering problem from day one. On full lock this car becomes a crab. It sounds like the tyres are being pulled off the rims plus the car hops and judders. The dealer principle at Sandown Motors has done nothing. Her response is she sell hundreds!! and her job is to sell the vehicle not sort out tech issues!! To get hold of AMG Technical in South Africa is impossible. Mercedes knows there is a serious issue with the right hand version but avoids taking responsibility. This car is *******!!! I have been a Merc/AMG client for 20 years plus.