Poor customer service

We took our Haval H2 luxury on Tuesday 17/10/2023 to Edenvale workshop because the tyre sensors are malfunctioning, the drive mode changes itself whilst the vehicle is in motion and the USB port is also malfunctioning. They told us that they don't have replacement parts. We requested a courtesy car because we can't afford to drive a car in that state moreover, my wife, the regular driver, is a 73 year old pension who wouldn't know what to do should it brake down in the middle of nowhere instead her weak heart would stop. Instead of being given one since we still under warranty, we being taken from pillar to post from 9 or 1o in the morning until now. This is the second time we experienced such bad treatment from this dealership simply because managers are using cars that should have been given to customers as private vehicles and it's normal for them. Please someone out there assist us.