Brand new car

Hi i bought a brand new Nissan micra 2021 model from 4 wheels Nissan Lichtenburg in August 2021 in 12 January I called them told them that I give me problem they said I must take it to nissan in rustenburg I did that in rustenburg they said they will at once done a service because it was already 14500 km so we agreed next day nissan Rustenburg call and said the are done I go to fetch a car when a come back the is white smoke coming from the car I call them again and they said I must take it back 2moro I did that they said I must leave it for them to monitor it I did so I spend whole month without even a courtesy car when I call them they sad they are waiting for authorization fo opening the engine I did ask them hw can they open a brand new car engine and they said they what to see what can cause then then I call my salesperson in Lichtenburg and she says to me she can't do nothing it's out of their hand then I called nissan southafrica tell them about my car then they said the gave then authority to open the car so I have to wait after a month and weeks nissan southafrica offer me a courtesy car they told me they have to order the engine and turbo I ask a gain how can that happened even now they did helped me to understand like now they tell me they are waiting for engine from overseas it will arrive in 13 March for me its unfair to me bcs I did bought a brand new car they must give me a brand new car bcs my car wa less than 6months and less than 15000km pls help I'm just a 38 lady who just bought herself first car knowing nothing about the cars